Renewable energy generation based on water waves

ABSTRACT

Methods, systems, and devices are disclosed for wave power generation. In one aspect, a wave power generator device includes a stator assembly and a rotor assembly encased within a tube frame. The stator assembly includes an array of inductor coils in a fixed position within a cavity of the tube frame and a plurality of bearings coupled to the tube frame. The rotor assembly includes a turbine rotor having a central hub and peripheral blades coupled to a high inertia annular flywheel that is moveably engaged with the bearings of the stator assembly, and an array of magnets arranged to be evenly spaced and of alternating axial polarity from one another extending from the annular flywheel into the cavity between the array of inductor coils, such that electric currents are produced based on magnetic field interaction of the magnets with the inductor coils during the rotation of the annular flywheel.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent document is a continuation of U.S. patent application Ser.No. 16/953,105, entitled “RENEWABLE ENERGY GENERATION BASED ON WATERWAVES”, filed Nov. 19, 2020, which is a continuation of U.S. patentapplication Ser. No. 16/684,909, entitled “RENEWABLE ENERGY GENERATIONBASED ON WATER WAVES”, filed on Nov. 15, 2019, which is a continuationof U.S. patent application Ser. No. 16/364,074, entitled “RENEWABLEENERGY GENERATION BASED ON WATER WAVES”, filed on Mar. 25, 2019, nowU.S. Pat. No. 10,480,481, which is a continuation of U.S. patentapplication Ser. No. 15/514,464, entitled “RENEWABLE ENERGY GENERATIONBASED ON WATER WAVES”, filed on Mar. 24, 2017, now U.S. Pat. No.10,253,746, which is a 371 National Phase Application of PCT ApplicationNo. PCT/US2015/052491, entitled “RENEWABLE ENERGY GENERATION BASED ONWATER WAVES”, filed on Sep. 25, 2015, which claims the benefits andpriority of U.S. Provisional Patent Application No. 62/055,141, entitled“RENEWABLE ENERGY GENERATION BASED ON WATER WAVES,” filed on Sep. 25,2014. The entire contents of the aforementioned patent applications areincorporated by reference as part of the disclosure of this application.

TECHNICAL FIELD

This patent document relates to systems, devices, and processes thatgenerate energy from wave power in a large body of water such as oceans,rivers or lakes.

BACKGROUND

Water waves carry kinetic energy and can be converted into electricityor other form of energy for proper use. Examples of usable water wavesfor energy conversion includes ocean surface waves, waves in rivers,lakes or reservoirs, or other large bodies of water.

SUMMARY

In some instances, wave power is used in water desalination processes orwater pumping processes, e.g., into reservoirs. Currently, wave power isnot widely employed on a large scale. For wave power energy solutions tobe widely adopted, new types of scalable systems are needed to providean alternative to fossil fuels, offering several advantages to fossilfuels including availability and renewability as an energy source, lackof greenhouse gas or pollutant emissions, and the capability of beingwidely distributed along coastlines, among others.

Techniques, systems, and devices are disclosed for power generationbased on water waves.

In one aspect, a wave power generator device to interface to anoscillating water column for converting marine wave power intoelectricity includes a tube including a support base on each end of thetube; a stator assembly including a circular array of inductor coilsfixed in position in a cavity of the support base, an annular ring trackcoupled to the support base in the cavity and configured to provide acircular track around which the circular array of inductor coils islocated, and bearings placed on a circular annular bearing-ring trackattached to the support base, the bearings operable to roll to allow asurface in contact with the bearings to move with respect to the annularbearing-ring track; and a rotor assembly including an annular cylinderflywheel structured to form a hollow interior and an outer cylindricalwall having a wide thickness to provide the annular cylinder flywheelwith a high inertia, a turbine rotor attached to the annular cylinderflywheel at a particular plane along the hollow interior, the turbinerotor structured to include a disk and a plurality of blades protrudingfrom the disk that pass through the outer cylinder wall of the annularcylinder flywheel into a cavity, and an array of magnets arranged to beevenly spaced and of alternating axial polarity from one anotherprotruding from the outer cylindrical wall of the annular cylinderflywheel such that the magnets move through the circular array ofinductor coils as the annular cylinder flywheel rotates with respect tothe annular ring track so that the relative motion between the magnetsand the inductor coils causes generation of electric currents in theinductor coils, in which the rotor assembly is engaged to the bearingson the circular annular bearing-ring track so that the annular cylinderflywheel is operable to rotate relative to the annular ring track byrolling motion of the bearings when airflow from wave energy enters thehollow interior of the rotor assembly and causes the turbine rotor torotate for conversion of the wave energy into the electric currents inthe inductor coils, and in which the tube encases the rotor assembly andthe stator assembly.

In one aspect, a wave power generator device includes a tube frameincluding a hollow interior and a first support base and a secondsupport base on each end of the tube frame, in which the first andsecond support bases are arranged to form a cavity along the peripheralof the tube frame; an array of inductor coils positioned at in thecavity for each of the first and second support bases; a plurality ofbearings coupled to each of the first and second support base operableto roll to allow a surface in contact with the bearings to move withrespect to the inductor coils; an annular flywheel structured to includean outer cylindrical wall adjacent to the first and second supportbases, the outer cylinder wall having a wide thickness to provide theannular flywheel with a high inertia; a turbine rotor attached to theannular flywheel at a particular plane of the hollow interior, theturbine rotor structured to include a disk and a plurality of bladesprotruding from the disk, in which the turbine rotor is coupled to theouter cylinder wall of the annular flywheel; and an array of magnetsarranged to be evenly spaced and of alternating axial polarity from oneanother, the array of magnets coupled to and protruding from the outercylinder wall of the annular flywheel and located in the cavity of eachof the first and second support bases in a gap between the inductorcoils, in which rotation of the annular flywheel causes the magnets tomove through gap between the inductor coils such that the relativemotion between the magnets and the inductor coils causes generation ofelectric currents in the inductor coils, in which the wave powergenerator device is structured to be interfaced with an oscillatingwater column, such that airflow expelled from the oscillating watercolumn caused from wave energy is able to enter the hollow interior ofthe wave power generation device and affect rotation of the turbinerotor for conversion of the wave energy into the electric currents inthe inductor coils.

In one aspect, a method for generating electricity from water waveenergy is disclosed. The method includes receiving water waves into anoscillating water column to produce an outward airflow from theoscillating water column as a result of the received water waves. Themethod includes receiving the outward airflow into an interior region ofa wave power generator device. The wave power generator device includes(i) a stator assembly and (ii) a rotor assembly encased within a tubestructure having a base frame at each end of the tube structure. Thestator assembly includes a circular array of inductor coils in a fixedposition with respect to the base frame in the cavity and a plurality ofbearings coupled to the base frame. The rotor assembly includes aturbine rotor having a central hub and peripheral blades coupled to anannular flywheel that is moveably engaged with the bearings of thestator assembly. The rotor assembly also includes an array of magnetsarranged to be evenly spaced and of alternating axial polarity from oneanother protruding outwardly from the annular flywheel and between thecircular array of inductor coils. The method includes generatingelectrical power at the wave power generator based on rotation of theannular flywheel on the bearings at least initially caused byoscillating airflow into and out of the interior region of the rotorassembly to initiate rotation of the turbine rotor in one direction,such that electric currents are produced based on the interaction ofmagnetic fields from the magnets with the inductor coils during therotation of the annular flywheel. The rotation steadily continues inabsence of or reduced wave energy from the water waves.

Those and other aspects, features and implementations are described ingreater detail in the drawings, the detailed description, and theclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A shows a diagram of an exemplary EiP wave machine (front and sideviews).

FIG. 1B shows a diagram illustrating a cross sectional view of theexemplary EiP wave machine including its internal components.

FIGS. 1C and 1D show illustrative diagrams of an oscillating watercolumn interfaced with an exemplary EiP wave machine to convert theairflow out of the OWC, caused by the rising and falling water wavesin/out of the OWC, into the electrical energy by the EiP wave machine.

FIG. 2A shows a diagram illustrating an exemplary EiP permanent magnetlinear synchronous machine (PMLSM).

FIG. 2B shows a diagram of an exemplary EiP synchronous generatormagnetic circuit.

FIG. 2C shows a diagram illustrating an exemplary PMLSM three-phasemagnetic circuit.

FIG. 2D shows a diagram showing a cross section of an exemplary C coreand fill factor.

FIG. 2E shows a diagram of an exemplary magnetic rotor expansion usingidentical magnets and pole pitch.

FIG. 2F shows a diagram of van der pol oscillation.

FIG. 2G shows a diagram of an exemplary negative resistance oscillator.

FIG. 2H shows a pseudo-schematic of an exemplary minimal EiP oscillator.

FIG. 2I shows an exemplary diagram depicting the essential EiP energyimbalance.

FIG. 3A shows a cross sectional diagram of the exemplary EiP wavemachine.

FIG. 3B shows an axial view diagram depicting the exemplary magneticrotor, high-inertia flywheel, and Wells rotor of an exemplary EiP wavemachine.

FIG. 3C shows a diagram depicting a 60 degree section of the magneticarray, and a cross section of rotor and flywheel.

FIG. 3D shows a diagram showing a front and cross-sectional view of anexemplary half of the housing.

FIG. 3E shows a diagram showing a rear view of an exemplary half of thehousing.

FIG. 3F shows a diagram of an exemplary EiP wave machine inductorsupport ring.

FIG. 3G shows diagrams depicting exemplary inductor specifications of anexemplary EiP wave machine.

FIG. 3H shows a diagram depicting an exemplary bearing ring as viewedfrom the flywheel.

FIG. 3I shows a diagram showing a closer view of exemplary bearings andhow they attach to the bearing ring.

FIG. 4A shows a circuit diagram depicting an exemplary PMLSM diodebridge.

FIG. 4B shows a schematic diagram showing the exemplary VSC and PMLSMstators.

FIG. 4C shows a schematic diagram of an exemplary the EiP oscillator forthe exemplary EiP wave machine.

FIG. 5A shows a diagram of an exemplary EiP distributed generationsystem architecture.

FIG. 5B shows a diagram of an exemplary EiP high voltage DC transmissionsystem.

FIGS. 6A and 6B show three-dimensional schematics of an exemplary windpower generator, referred to as the electronic inertial power (EiP) windmachine.

FIG. 6C shows a cross sectional diagram depicting the lower portion ofan exemplary EiP wind machine.

DETAILED DESCRIPTION

Techniques, systems, and devices are disclosed for marine wave powergeneration. In some implementations, a wave machine includes anintegrated turbine and generator converting oscillating airflow fromwave energy into usable electric power.

Marine renewable energy conversion devices of a certain type, extractpower from the oscillating water column (OWC) of breaking waves. Themoving mass of the water column in a confined space (plenum) compressesair through a relatively narrow opening (venturi), where a turbineconnected to an electrical generator shaft makes power from the airflow.Using a Wells turbine, the water column rises and falls with each waveas airflow periodically reverses direction, while the rotor spins in onedirection.

In quarter-scale models operating in wave tanks, the direct drive turbogenerator appears to operate quite efficiently. However, when a Wellsturbine is scaled up to full size and power, a slower rotating shaftwith massive mechanical torque becomes unsuitable for efficientelectrical generation, presenting a road block to utility-scale OWCpower.

To extract power from a slow rotor with high mechanical torque, thegenerator implements many magnetic poles, along with correspondingamounts of steel core and copper windings. The generator radius is setto be sufficiently large to accommodate all the poles, but this comeswith a trade-off as shearing forces on the central shaft limit size andtorque. If steel cores are used for greater efficiency with a brushlesspermanent magnet rotor, magnetic attraction across a large radiusincreases starting torque. So, direct drive generators must compromisepower output for less than optimal electromagnetic torque as sizeincreases.

Moreover, direct OWC power is naturally unsteady, with short peaks ofwave energy followed by longer gaps of no energy. To be truly “wave towire”, the turbine/generator must produce steady electrical output. Eventhough the wave cross section is sinusoidal, low turbine efficiencycombined with the physics of electrical generation produce only briefsurges of electric power during each wave cycle.

The disclosed technology provides a total solution for utility-scale OWCpower. For example, the disclosed technology provides: (i) efficientelectrical generation for a large Wells turbine, using an electricalmachine of modular structure that is adaptable and scalable to hightorque at slow speed; (ii) permanent magnet brushless design with widegap tolerance and low magnetic friction between steel cores and rotormagnets; (iii) high-speed electronic power control that leverages highrotor inertia for ride-through between wave peaks, delivering usefulpower under intelligent network control; and/or (iv) reliable andfault-tolerant design, with a modular and redundant architecture, socomponent failures cause only reduced power output while the machinekeeps running; failed components are replaced during scheduled serviceintervals.

Disclosed are methods, systems, and devices of the present technologyfor converting wave energy to electricity using a wave machine of thepresent technology to operate as a super-efficient turbine and generatorfor any size rotor. The disclosed wave power generators are alsoreferred in this patent document to as the electronic inertial power(EiP) wave machine. The EiP wave machine provides a platform for directgeneration, storage, and stabilization of electric power from a singlemoving mass, which can be caused to move based on fluid wave power.

In one aspect, a wave power generator device to interface to anoscillating water column for converting marine wave power intoelectricity. The wave power generator device includes a sealed tubeincluding a support base on one or both ends of the tube; a statorassembly; and a rotor assembly, in which the sealed tube encases therotor assembly and the stator assembly. The stator assembly includes acircular array of inductor coils fixed in position over the supportbase, an annular ring track coupled to the base support and configuredto provide a circular track around which the circular array of inductorcoils is located, and bearings placed in the circular track of theannular ring track to roll in the circular track to move around theannular ring track. The rotor assembly includes an annular cylinderrotor structured to form a hollow interior and outer cylindrical wallhaving a wide thickness to provide the annular cylinder rotor with ahigh inertia, a turbine rotor attached to an interior surface of theannular cylinder rotor at a particular plane along the hollow interior,the turbine rotor structured to include a disk and a plurality of bladesprotruding from the disk, and an array of magnets arranged to be evenlyspaced and of alternating axial polarity from one another on the outercylindrical wall of the annular cylinder rotor such that the magnets tomove through the circular array of inductor coils as the annularcylinder rotor rotates over the annular ring track so that the relativemotion between the magnets and the inductor coils causes generation ofelectric currents in the inductor coils, in which the rotor assembly ispositioned over the annular ring track and engaged to the bearings inthe circular track so that the annular cylinder rotor is operable torotate relative to the annular ring track by rolling motion of thebearings in the circular track when airflow from wave energy enters thehollow interior of the rotor assembly and causes the turbine rotor torotate for conversion of the wave energy into the electric currents inthe inductor coils.

The disclosure of this patent document is organized with the followingtop-level headings:

Section 1: Introduction. This section includes a general overview of theEiP wave machine and exemplary applications.Section 2: Operation Principles. This section includes a description ofhow the disclosed technology works, and presents mathematical models forvarious aspects of operation.Section 3: Mechanical Specification. This section includes a descriptionof exemplary embodiments of the EiP wave machine physical form andfunction.Section 4: Electronics Hardware Specification. This section includes adescription of exemplary embodiments of the EiP electronic architecture.Section 5: System Architecture. This section includes a description ofexemplary system integration and networking concepts.Section 6: Programming Considerations. This section includes adescription of an exemplary EiP wave machine software interface,including programming of EiP machine networks.

1. Introduction

1.1. EiP Wave Machine Overview

Disclosed are electronic inertial power generation devices, systems, andmethods that produce electrical energy from environmental sources suchas waves, wind, and other ‘clean’ or ‘green’ energy sources. Variousembodiments and implementations of the disclosed electronic inertialpower generation technology (or EiP technology) are described,particularly wave power generators that are scalable on a local scale,e.g., referred to as the EiP wave machine. The EiP wave machine caninterface to an oscillating water column (OWC) for converting marinewave power into high velocity airflow, capable of driving the EiP wavemachine rotor for energy conversion for a wide range of wave conditionswithout mechanical adjustment. The disclosed EiP technology adaptsdirect electrical generation to a Wells-type rotor, so power can beextracted from fluctuating changes in wave power (e.g., high tide to lowtide) in random directions to produce steady useable electrical poweroutput.

The EiP wave machine is an energy conversion device, which efficientlytransforms mechanical torque with high inertia to electromagnetictorque, producing useful power within a fraction of rotation, e.g., andcan do this with one moving part. The EiP wave machine includes apermanent magnet generator with many poles and core windings integratedwith the aerodynamics of a Wells-type rotor. For high inertia, athick-walled cylinder attaches to the blade tips. The outside of thecylinder becomes the “shaft” for generator magnetics populating thecircumference. With no central shaft and main bearing, unlimited torqueresponse is possible.

In implementations of wave energy to electrical energy conversion usingthe disclosed technology, an exemplary EiP wave machine is interfaced toan oscillating water column (OWC) or wave energy capture device. Forexample, there are typically two types of OWC wave energy capturedevices. One example of an OWC device includes a hollow air chamber withan opening in the sea water and an exit to the atmosphere to expel airfrom the chamber. The outward airflow (e.g., expelled from a channel orthe chamber) of the OWC device can be interfaced with a pipe flange thatfits the wave power generator device, e.g., such as the EiP wave machineof the present technology, as discussed here. When the water wave peaksoccur, the air is compressed and forced out of the OWC and into free airthrough the EiP wave machine. In the EiP wave machine, for example, therotor responds by turning in a certain direction (e.g., depending onwhich end of the EiP wave machine is attached to the OWC pipe flange) asthe compressed air flows out through the EiP wave machine. As the waterwave recedes, the air chamber of the OWC is decompressed and air isdrawn back through the EiP wave machine as the rotor continues to spinin its current direction. Successive wave motions create an oscillatingair flow in and out, while the rotor continues to spin in a constantdirection, at a regulated speed fortified by the rotor flywheel mass andelectronic interactions to create steady power output.

Another example of an OWC wave energy capture device uses dual airbagsattached to the seafloor with a tube from each airbag, which areattached at one end of the wave power generator device, e.g., such asthe EiP wave machine, as discussed here. As a wave passes over theairbags of the OWC device, air is forced from one bag to the otherthrough the EiP wave machine and back again, producing rotor motion inone direction supported by flywheel inertia and electronic interactions.The outward airflow (e.g., expelled from tube) of the OWC device can beinterfaced with a pipe flange that fits the EiP wave machine. Thedisclosed the EiP wave machine maintains rotor speed in between wavepeaks for achieving a steady electrical output. FIG. 1C shows anillustrative diagram of an oscillating water column interfaced with anexemplary EiP wave machine 100 to convert the airflow out of the OWC,caused by the rising and falling water waves in/out of the OWC, into theelectrical energy by the EiP wave machine 100. The EiP wave machine 100can be configured with other examples of OWC devices, systems, andstructures, such that the airflow output of the OWC is interfaced withthe hollow interior of the EiP wave machine 100 to affect the rotationof the rotor assembly. For example, FIG. 1D shows another illustrativediagram of an oscillating water column interfaced with the EiP wavemachine 100, in which the EiP wave machine is oriented perpendicular tothat shown in FIG. 1C.

FIG. 1A shows a diagram illustrating front and side views of anexemplary EiP wave machine 100. FIG. 1B shows a diagram illustrating across sectional view of the EiP wave machine 100 showing at least someof its internal components. From input to output, the structure issymmetrical and identical with respect to inflow and outflow of air fromthe OWC wave energy capture device. The EiP wave machine 100 featured inFIGS. 1A and 1B is configured to have a circular geometry with respectto the front view and a one meter diameter of the rotor assembly; butthe EiP wave machine 100 can be configured to other curved geometriesand larger or smaller dimensions. The EiP wave machine 100 includes anelectronic inertial power generation unit 110 of the disclosedtechnology. The electronic inertial power generation unit 110 includes aframe 111 structured to form a sealed tube including a support base ateach end of the tube. The frame 111 includes watertight covers 121(e.g., also referred to as watertight cover straps) at the ends of thetube that attach the support base of the frame 111 forming a tight sealto prevent water or fluids to leak inside the tube interior of theelectronic inertial power generation unit 110. In some embodiments, theframe 111 includes threaded holes 119 along an outer surface of thesupport base configured to fit a standard pipe flange bolt pattern. Insome implementations, for example, EiP wave machine 100 can include anexternal casing 120 that encloses, at least partially, the electronicinertial power generation unit 110 in the external casing 120. In suchembodiments including the external casing 120, the casing 120 mayinclude an exterior shell having one or more openings to access variousregions of the interior, in which the openings can be covered by awatertight covers (e.g., such as the watertight cover straps 121).

The electronic inertial power generation unit 110 includes a statorassembly. The stator assembly includes an array of inductor coils 102(e.g., also referred to as ‘inductors’) located in a cavity of thesupport base and fixed in position with respect to the support base ofthe frame 111. The stator assembly includes an annular inductor ringtrack 112 (e.g., also referred to as ‘inductor rings’) coupled to thesupport base in the cavity and configured to provide a circular trackaround which the circular array of inductor coils 102 is located. Thestator assembly includes an array of bearings 103 (e.g., also referredto as ‘bearings’, which may include vertical support bearings and/orside support bearings) arranged in a fixed position with respect to thesupport base of the frame 111 and coupled to an annular bearing ringtrack 113 (e.g., also referred to as ‘bearing rings’) attached to thesupport base, such that the bearings 103 are able to move (e.g., roll)around the annular bearing ring track, e.g., providing a circular trackaround which a flywheel assembly may rotate. Bearings in the radialdirection support the rotor, while bearings in the axial directionrestrict lateral motion of the rotor.

The electronic inertial power generation unit 110 includes a rotorassembly. The rotor assembly includes an annular cylinder flywheel 114structured to form a hollow interior and outer cylindrical wall having awide thickness to provide the annular cylinder flywheel 114 with a highinertia. The rotor assembly includes a turbine rotor 115 attached to theannular cylinder flywheel 114 at a particular plane along the hollowinterior, the turbine rotor structured to include a disk or hub 115A anda plurality of blades 115B protruding from the disk 115A that passthrough the outer cylinder wall of the annular cylinder flywheel 114into the cavity of the support base. The rotor assembly includes anarray of magnets 104 arranged to be evenly spaced and of alternatingaxial polarity from one another on an array of outer protrusionsstemming from the outer cylindrical wall of the annular cylinderflywheel 114. The array of magnets 104 are arranged such that, when theannular cylinder flywheel 114 rotates with respect to the statorassembly, the magnets 104 moves through the circular array of inductorcoils 102 as the annular cylinder flywheel 114 rotates on the bearings103 over the annular bearing-ring track 113 so that the relative motionbetween the magnets 104 and the inductor coils 102 causes generation ofelectric currents in the inductor coils 102.

The rotor assembly is positioned with respect to the annular ring track112 and engaged to the bearings 103 in a circular track so that theannular cylinder flywheel 114 is operable to rotate relative to theannular ring track 112 by rolling motion of the bearings 103 in thecircular track when airflow from the OWC wave energy capture devicepasses into and out of the hollow interior of the rotor assembly throughthe pipe flanges and causes the turbine rotor to rotate for conversionof the wave energy into the electric currents in the inductor coils.

An example embodiment is described, also with reference to FIGS. 1A and1B. At the center of the EiP wave machine 100 includes a hub disk 115Awith five airfoil blades 115B to form an ideal “high solidity” Wellsrotor, e.g., which can be configured without a rotary shaft. In thisexample, the rotor is configured to be at least one meter in diameter.The blade tips are attached midway inside a hollow cylinder, which addsthe high inertia flywheel 114 to the Wells rotor, riding on the ring 113of bearings 103 at each end. Protruding from the outside of the flywheelis an annular ring containing the permanent magnets 104 of alternatingaxial polarity. As the rotor spins, rapidly rotating lines of magneticflux generate electric power as they pass through a magnetic gap betweenstationary inductor pairs, organized as modular synchronous machinesaround the circumference of the rotor. A watertight cover 121 and frame111 encases the inductor array 102, rotor turbine, magnets 104 andflywheel 114, and bearings 103, while also providing standard pipeflange interface to the OWC air plenum. For example, two wires (e.g., DCpositive and negative) and fiber-optic cable can attach to an onshoreaggregation point, where DC power is combined under network control andprepared for grid transmission.

The exemplary EiP wave machine is a mechanical device that can includeone moving part: the rotor. The rotor includes a cylinder with thickwalls for high inertia (e.g., the flywheel). On the inside, halfwaybetween cylinder ends, for example, a Wells turbine rotor is attached.On the outside, in the same plane with the Wells rotor, for example, isthe magnetic rotor annulus, including a ring of magnets forming amagnetic track around the outside of the cylinder of magnet thickness. Atube frame encapsulates the rotor in a sturdy structure with pipeflanges that provides a framework for stationary inductors (stators)paired on either side of the magnetic rotor. The transition between pipeflange diameter and inner flywheel surface creates a venturi for theWells-type rotor. As the rotor slowly spins, magnetic flux circulates athigh speed through stator pairs, instantly generating pure sinewave ACpower, with voltage and frequency increasing with rotor speed(synchronous power). Synchronous power from a modular array of statorsis connected to electronics located behind the inductors in a sealedcompartment, each module is wired together in series for high voltage DCoutput.

In one example embodiment, the EiP wave machine rotor can be configuredto be about 1.4 meters in diameter, supporting eighty magnetic polepairs (e.g., 160 magnets). The following figures in this patent documentare based on this exemplary design, and demonstrate implementations ofthe present technology for marine renewable energy generation. Thisexemplary embodiment of the EiP wave machine represents a minimumpractical size of EiP wave machine 100. The disclosed technologyincludes various designs of the EiP wave machines that are naturallyscalable to much larger sizes, e.g., to match the power of any OWC site.

1.1.1. Enhanced Wells Turbine Performance

For example, some main differences between a Wells turbine and an EiPwave machine are the integrated flywheel and lack of central rotaryshaft. Positive aerodynamic side effects include the elimination ofstalling under high air flows, and improved internal pressuredifference. The inner flywheel surface straightens out turbulenceentering the rotor, and cuts off air leakage around blade tips, directedtoward higher working pressure on the intake side. The hub disk with noshaft allows turbulent flow on the back side of rotor blades to organizeinto a wake vortex that increases the pressure drop for increasedmechanical power to overcome stall conditions.

The greatest failing of a Well turbine is high startup speed. EiPtechnology starts and maintains rotor speed, enhancing flywheel inertiausing one module dedicated to motoring. In combination with flywheeleffect, average rotor inertia remains constant between wave peaks as EiPspeed regulation injects timely bursts of motoring thrust as a controlmechanism.

1.1.2. Utilizing the Inertia of a Massive Rotor

A larger radius Wells rotor provides a dramatic increase in mechanicalpower, although at slower rotation speed. Inertia and torque increasewith the square of the radius, along with overall weight. In a standardWells turbine, a large diameter rotor cannot efficiently run a generatoron a central shaft for two reasons: slow rotation speed and excessivetorque. Slow speed requires many generator poles, which requires a largegenerator radius to accommodate all of the coils and magnets. Highmechanical torque from the rotor limits the electromagnetic torqueresponse because of shaft stress. EiP technology converts power directlyon the radius, not the center, where enough electromagnetic componentscan produce maximum power production at low rotor speed without breakingthe rotary shaft.

Energy storage flywheels typically use a rotor of small radius andoperate at high speed, because energy storage potential increasesexponentially with speed. In EiP technology, the flywheel is a heavyrotating cylinder with a large radius; even at low speed, accumulatedinertia becomes significant, magnifying the energy potential of smallchanges of angular velocity. EiP technology recirculates power fromexcess inertia toward controlling inertia, further enhancing theflywheel storage time by promoting speed up and retarding slow down inresponse to operating conditions.

High inertia delivers peak power output resembling a massive batterybank. EiP wave machines eliminate the need for batteries and othertemporary storage. For example, in the short term, high inertia isleveraged to stabilize power output between wave peaks. For long-termstorage onshore, the battery bank could be replaced by fuel cells, forexample, allowing inertia to handle load peaks.

1.1.3. Modular Architecture

EiP technology enhances power production from less weight and cost ofmaterials, through parallelism with a modular architecture. EiPtechnology breaks down a massive amount of magnets, iron, copper, andsilicon into efficient modules that produce more power in aggregate thana monolithic design. EiP technology includes a new three-phase generatormodule, stacked around the rotor edge, where thrust force is amplifiedby the rotor radius. In other words, the equivalent electrical input fora rotary machine is multiplied by the radius upon which the EiP moduleoperates.

Each module is a linearized three-phase machine that receives excitationfrom a magnetic track around the rotor, instead of a rotary shaft. Usingthree split inductors, half on one side and half on the other, witheight rotor magnets passing between at any moment, EiP technologydefines a specific physical layout for magnets and stators that enforcesthree-phase synchronous operation between any three adjacent stators.Each module is synchronous, and compatible with standard three-phaseelectronic rectifiers and industrial drive circuitry.

In some embodiments representing the most minimal configuration, forexample, three modules are arranged around the rotor one hundred twentydegrees apart. For more power, four can be arranged ninety degrees apartin quadrature. Six can form a star configuration with sixty degrees ofseparation. The number can be expanded geometrically. In the EiP wavemachine, the entire circumference is fully populated with generatormodules wired in series, for maximum voltage to drive the long cable runto shore where power is combined with other EiP wave machines.

1.1.4. Direct Conversion of Electromagnetic Torque to Power

Synchronous generation allows a sensorless technique that reads timingcues directly from raw DC power, using digital signal processing.Electromagnetic torque control occurs faster than changes in rotortorque, so peak energy from a violently breaking wave is smoothlyabsorbed as slow change in rotor speed.

Smooth torque control gently speeds up the rotor, storing excess energyas inertia, which accumulates dramatically with speed. One generatormodule is selected to operate as a motor to boost rotor inertia as aregulation mechanism that responds faster than resource and loadchanges. Essentially, the EiP machine contains many smaller electricalmachines sharing and combining power on a DC network. For speed control,one module acts as a motor while the others generate. The motoringmodule maintains speed under load by injecting bursts of thrust appliedto the rotor radius. At a certain speed, energy from inertia exceeds theload and electrical/mechanical overhead, creating a condition referredto as “overhauling”, from which power is harvested by reverse motoring,when the motoring module intermittently becomes a generator.

1.1.5. Energy Storage By Electronic-Mechanical Oscillation

EiP technology combines energy from waves and inertia with electronicactions, to spawn the EiP oscillation. Rotational inertia allows therotor to resist changes in speed: acceleration with a sudden blast ofenergy, or deceleration under changes in electrical load. The EiPoscillation amplifies inertial effects in a positive direction:increasing the uptake of wave power from a heavy rotor while reducingslowdown from peak loading. In effect, multiplying rotor flywheel energystorage time using only the tiny amount of power required to keepelectronics running.

1.1.6. Cleaner and More Efficient Power Generation

When all of the windings of a large generator are stitched together,they pick up stray magnetic fields leaking out of the rotor. Theresulting AC output is ragged, full of rotor harmonics, which produceheat, not useful power. Each synchronous generator module produces puresine waves. EiP technology breaks up and isolates core elements ascompact segments, using a novel electronic/magnetic design thatconcentrates stray magnetic fields. The result is a modular synchronouspower with low harmonic content, converted to DC and combined with othermodules at maximum efficiency.

With a tiny amount power from the grid, the EiP wave machine rotor staysspinning. In “standby” mode, rotor inertia and aerodynamics pluselectronic speed control hyper-sensitize the uptake of energy. Whilepower from the grid trickles in, the EiP wave machine delivers powerbacked by rotor inertia and electronics, with vast surge potential. Highsurge power stabilizes peaks and dips for solid grid-quality power.

1.1.7. Simple Electrical and Control Interface

The EiP wave machine presents a simple interface to onshore power: highvoltage DC power and ground. Embedded intelligence in the EiP wavemachine can be controlled by a direct fiber optic cable. For example,such electrical and optical communications connections can includecopper wire and/or fiber optic cables, which may all share a singleburied conduit from the EiP wave machine to shore, where power fromother machines can be combined and fed to the grid. Onshore, the EiPnetwork can be managed to extract maximum output from an entire networkof EiP wave machines in a marine renewable energy array.

1.2. Reliable and Scalable Modular Design

One of the greatest failings of all turbines with a central shaft isscalability to larger sizes. Smaller models seem to work great in thelaboratory, but when the radius is expanded the speed of rotation slowsand mechanical torque increases to a point where efficient electricpower production is impossible. In the disclosed EiP wave machinetechnology, electric power generation naturally expands with rotor size.Slowness is not a problem, since as the radius expands, more space iscreated for more power generating parts at a higher magnetic frequency.The EiP design principles are scalable, expandable for maximum energyuptake and power output for an EiP wave machine of very large size.

1.2.1. Fault Tolerant Design

For reliability, the EiP wave machine has only one moving part;mechanical systems can be replaced with magnets, coils, and electronics.Direct drive requires no mechanical gearboxes, slip rings, orcommutation, for example.

Main bearing failure causes the most downtime in conventionalgenerators. In contrast, for the EiP machine, the hollow centereliminates the main bearing, using multiple smaller bearings that spreadthe load around the rotor circumference, where the load is shared byredundant bearings. For example, if a bearing should fail, overalloperation is unaffected.

1.2.2. Generator Modules

The second highest source of downtime is electrical failure. The EiPwave machine splits the generator into discrete inductors, e.g.,organized as three-phase modules sharing a common DC connection.Integrated rectifiers convert three-phase AC into DC, isolating eachgenerator module from the next. If one should fail, for example, themachine keeps running under reduced power output, not total shutdown.

1.2.3. Low Cost and Manufacturable Design

Through EiP technology, the size of all electromagnetic elements areoptimized, fine-tuned for maximum power production at least weight andcost, replicated in a modular design. The EiP wave machine can be builtfrom common materials, e.g., like stainless steel, aluminum, copper,epoxy resin, and magnets. Structural parts can be fabricated from lasercut plate stock and machined castings. Other parts, like magnets,inductor cores, coils, electronics, and bearings, can be selected from awide range of original equipment manufacturer (OEM) sources. A primedirective of EiP technology is to build locally, assembling EiP wavemachines near the place of installation, using non-exotic facilities,skills, and fabrication techniques.

1.3. EiP Spontaneous Networking Technology

The disclosed technology specifies a network interface in various media(e.g., wireless, wired, or fiber optic). In the exemplary EiP wavemachine, fiber optics are chosen for monitoring and control of the EiPwave machine from a convenient location. Using this interface, multipleEiP wave machines can operate as “spontaneous” networks, linked bylocation and responsive to real-time power demands. Power conditioningis a byproduct of EiP wave machine architecture, stabilizing delivery ofmarine renewable energy at a local level. EiP wave machines onspontaneous networks of OWC arrays capture the vast energy potential inlarge swells. For example, every EiP wave machine on the network can beconfigured to share its status to all others, tapping into a real-timestream of wave and grid conditions, through which all EiP wave machinescan synchronize power storage and regulation. For example, as excesspower is created by one machine, another instantly absorbs it, workingwith all other EiP wave machines on the array to locally balance powerdemands.

1.3.1. Local Solution for Backup and Energy Storage

Spontaneous EiP wave machine networks transparently take over when gridpower sources falter. The heavy rotor combined with high speednetworking, provides enough energy to ride through wave peaks. Incombination with onshore power from EiP wind machines and solar panels,EiP technology delivers the solution for sharing locally generatedrenewable energy, with low cost and minimal impact. It is envisionedthat widespread adoption of EiP technology will eliminate the need forlarge distant powerplants, huge transformers, and long inefficienttransmission systems. When many EiP wave and wind machines are combinedon the network, for example, their combined electromagnetic torquerepresents tremendous instantaneous power capacity to meet load demands,or back down gently when resources are low.

1.3.2. Pathway to 100% Renewable Power Grid

Through EiP technology, distant hydropower and wind farms can be used topower the long-range transmission system, e.g., allowing power tonaturally fluctuate while local EiP wave and wind farms, and rooftopsolar, actually deliver power and maintain energy reserves. It isenvisioned that EiP technology can provide the pathway to one hundredpercent renewable grid power systems, where sidecar powerplants areeliminated, allowing renewable resources to ebb and flow, as spontaneousnetworks of EiP machines provide seamless power delivery.

2. Operation Principles

EiP technology includes a specific arrangement of magnetics plusembedded electronic control (e.g., electronics) for a modularthree-phase linear synchronous machine. Modules (e.g., identicalmodules) are combined around the rotor circumference to create a largepermanent magnet generator, e.g., with one module dedicated to motoringoperations for rotor inertia control. The magnetic circuit designguarantees three-phase excitation for any three adjacent stators, forexample, which can be equally spaced around a magnetic track in therotor. Each module generates full power at fractional rotor speed.Modules combine to form an EiP machine, duplicated around the rotor ingroups, presenting massive electromagnetic torque potential. Total poweris the sum all modules, for example, like locomotives on a circulartrack, thrust force from each one acts upon the rotor radius for maximumtorque response to rotor mechanical power. The EiP machine deliverselectromagnetic torque more quickly and powerfully than conventionalgenerators and transmissions.

2.1. EiP Wave Machine: Ultra High Efficiency Axial Flux Generator

Axial magnetic flux, in parallel with the center of the rotor, providesa simple way to generate power. Most permanent magnet designs use onlycopper coils with surface mounted magnets that rotate around. Thiseliminates the effects of magnetic drag from attraction to steelinductor cores, reducing the minimum air speed for startup. However,this design fails to efficiently concentrate rotor flux toward electricpower production.

EiP technology provides a new electrical energy generation machine: amodular high torque slow speed axial flux generator, with interiorpermanent magnetic poles, and no central shaft. EiP technology advancesaxial flux generator design far beyond normal limits, concentrating allmagnetic flux toward synchronous power, maximizing electromagnetictorque from the least amount of copper and steel, unlimited by shearingstress on a central shaft.

The EiP machine combines three-phase modular magnetics with embedded EiPoscillator electronics, to convert sudden fluctuations in mechanicaltorque to stable electric power backed by rotor inertia. The modularapproach provides the best way to adapt efficient power generation to alarge and slow-moving Wells rotor.

2.1.1. No Drive Shaft, Unlimited Torque

One primary difference between the EiP machine and other largegenerators is greater electromagnetic torque potential because of nocentral shaft, where shear strength limits thrust on a large radius. TheEiP technology includes modular magnetics match mechanical torque at therotor's edge with overwhelming thrust force, e.g., instead of twistingand breaking a shaft. Also, for example, the bearing load is spreadaround rather than centralized, for fault-tolerance andhigh-reliability.

2.1.2. Load Controlled Rotor Speed

EiP technology includes regulation of the rotor speed by electricalloading on the DC output, or by motoring operations using a dedicatedmodule in parallel with generating ones. Loading slows the rotor, whileair power speeds it up. Using instantaneous bursts of forward andreverse motoring, total inertia is maintained as speed changes occur ina controlled fashion.

2.1.3. Enhanced Flywheel Storage Through Exemplary OscillatorElectronics

The EiP magnetic rotor represents the ideal flywheel for high torque atslow speed, naturally bolstering air power uptake. Embedded EiPoscillator electronics inject motoring thrust response in a fraction ofrotation, faster than mechanical speed changes. This converts a widedynamic range of wave and load conditions to gradual rotor speedchanges.

When load is less than airflow plus inertia, electronic interactionsextend inertial storage time beyond the flywheel storage effect. Asrotor speed goes up and down in a relaxation oscillation, it directspower from airflow from wave energy and inertia toward electrical loadsplus rotor speed regulation. A small change in rotor speed correspondsto a large change in energy potential.

For even greater storage time, for example, clusters of EiP wavemachines linked by EiP spontaneous networking bounce power from excessinertia between machines. Over a wide geographical area, storage timeexpands, providing the foundation for 100% local renewable power.

2.2. Magnetics Design

Compromises in generator magnetics design are required by direct driveWells machines to overcome the following limitations to efficiency. Forexample, slow rotor speed means more magnetic poles, so the generatorradius must be larger. Stator cores must be near the poles; magneticattraction acting on a large radius creates excessive cogging force,forcing higher start up air speed. Stator windings and monolithic coremust encapsulate the rotor circumference, which produces an excessivelyheavy machine. Long stator windings generate harmonics from magneticrotor leakage flux. Massive electromagnetic torque acting on a largeradius can destroy a central shaft.

The disclosed EiP magnetics design conquers these limitations withoutreducing efficiency. Cores are segmented and arranged to form discretepermanent magnet synchronous machines. The arrangement of cores vs.magnets reduces the cogging force. Segmented cores exhibit less heatloss from eddy currents at higher frequency than a monolithic core.Synchronous power is clean, producing pure sinewave output. In someembodiments, for example, an exemplary EiP modular design specifies athree-phase magnetics architecture with integrated electronics thatisolates and concentrates stray rotor flux. Magnetic flux rotatesbetween core elements using a linear design requiring no driveshaft orgearbox.

2.2.1. Permanent Magnet Synchronous Power

A synchronous generator produces sine wave AC power, of increasingvoltage with rotor speed (n). The frequency (f) increases as well; howquickly depends on the number of magnetic poles (p), as shown in thefollowing Equation 2-1: Synchronous Power Frequency and Magnetic Poles.

f=p n/60  (Eq. 2-1)

In the exemplary EiP machine, pairs of magnets are embedded withalternating polarity, to form one generator “pole pair”. Using the aboveformula on the EiP wave machine rotor, e.g., with 160 magnets forming 80pole pairs, spinning at one revolution per second (e.g., 60 RPM),produces AC power at 80 Hz (e.g., three quarters rotor speed=60 Hz). At1.5 revolutions per second, the nominal operating frequency is 120 Hz.Since each stator interacts with two pole pairs, four magnets passbetween in one cycle, doubling the frequency of the induced voltage.While the mechanical angle between stators and magnets is 30 degrees,the electrical angle is 60 degrees. This is an advantageous designchoice, which doubles the electrical excitation of the stators at slowrotor speed.

The exemplary EiP magnetics design partitions a massive steel core intoisolated silicon steel cores, with thin laminations to reduce eddycurrent loss, organized as modular three-phase machines around therotor. The synchronous design guarantees production of smooth pure sinewaves (non-trapezoidal) in proper phase by concentrating all magneticflux, axial, transverse, and leakage, toward the fundamental generatorfrequency, for low losses. Electronic rectifiers isolate stator windingsthat share a common DC link. Distributed core elements with integratedrectifier, and modular three-phase format, present a new magneticdesign, e.g., for maximum power with highest efficiency, at the finestlevel of control possible. Modules can be combined to match the EiP wavemachine configuration.

2.2.2. EiP Permanent Magnet Linear Synchronous Machine (PMLSM)

When rotary four-pole three-phase stators and magnets are laid outinline, the EiP permanent magnet linear synchronous machine (PMLSM) isdefined. Relative size and placement of magnets and stator coresminimize cogging torque and enforce three-phase operation between anythree adjacent stator pairs, drawing excitation from rotating magneticfields of eight magnets passing between. In the rotary and linearmodels, a thirty-degree mechanical relationship between inductor corefaces and pole pairs produces an electrical angle between phases ofsixty degrees. Wye connection between the stators provides one hundredtwenty degree three phase operation.

FIG. 2A shows a diagram illustrating an exemplary EiP permanent magnetlinear synchronous machine (PMLSM), which shows the relationshipsbetween magnets and stationary inductors (stators) depicting themagnetic vs. mechanical cycle of an example three-phase grouping. Thediagram of FIG. 2A shows top and side views of the linear arrangement ofcomponents in the EiP PMLSM, on a short section of magnetic track, whichcorresponds to one three-phase magnetic cycle. The diagram shows how thephysical layout of this exemplary embodiment translates to dynamicthree-phase operations. The upper half of the diagram shows the toplayer of stators opened up like book pages to indicate the pattern ofmagnetic poles to stator legs. The lower half shows the view at therotor edge. The physical placement of stators vs. magnets is compact,with a narrow mechanical angle. The electrical angle fits thethree-phase model, twice the mechanical angle because magnetic poles arebuilt from oppositely polarized pairs of magnets. Excitation fromrotating magnetic fields with respect to stator cores is twice theelectrical angle, for full three-phase wye operation.

For example, each EiP PMLSM is like a linear positioner optimized forpower production, with 3 stators forming the “mover”, and four magneticpoles embedded in slots around the rotor circumference acting as the“track”. Permanent magnets are equal in width and thickness, inalternating axial polarity, separated by magnet width. Stators polefaces match the footprint of two magnets, on “C” cores made from 3%silicon steel laminations. Two C cores on opposite sides of the rotor,with equal windings on each leg, wired in series above and below therotor magnets, form one stator. A given rotor circumference supports acertain number of stators and magnets equally spaced around the rotor,partitioned into three-phase groups. Magnet size defines statordimensions, and the total number that fit around the magnetic track. Theratio of four magnetic poles to three inductor cores, evenly spaced,minimizes cogging (torque ripple), where magnetic pull on oneinductor/pole pair is balanced by three magnet pairs pulling on twoinductor cores.

2.2.3. EiP Synchronous Generator Magnetic Circuit

The disclosed EiP magnetic circuit uses C cores to concentrate magneticfields from rotor flux to synchronous AC power. Rotor harmonicsreinforce the fundamental frequency, for optimum efficiency. The C coresare basically a split transformer core, with an extended gap toaccommodate the magnetic rotor in between.

FIG. 2B shows a diagram of an exemplary EiP synchronous generatormagnetic circuit of the present technology for one leg in thethree-phase EiP machine, as viewed from the side. In the diagram of FIG.2B, magnetic lines of flux from permanent magnets follow the path ofleast resistance from north (N) to south (S). Axial flux is conducted bymagnetic steel, strengthening as core faces line up, eventually tosaturation. Embedded rotor magnets of opposite axial polarity, separatedby a distance equal to width and thickness, provide a secondary magneticcircuit for leakage flux. In combination with the relative motion of Ccores, this secondary circuit concentrates rotor leakage magnetic fieldstoward synchronous power.

At minimum gap, e.g., where core faces line up with magnets, maximumflux density saturates upper and lower core halves through four coils,wired in series for maximum voltage at leads L1 and L2. L1 connects toone leg of the three-phase wye (U, V, or W), L2 is the common connection(C). Each coil is wound with an identical number of insulated motor wireturns, of gauge and length appropriate for a given winding area. Voltagedrops to zero as the core lines up with space between magnets, then fullnegative as cores align with magnets of opposite polarity, producing oneAC cycle.

In this example design, the C core saturates easily in direct proximitywith a magnetic pole pair, flipping rapidly with rotor motion. Thismeans a narrow magnetic gap is not required for full voltage, whichallows for looser mechanical constraints on rotor motion. This enhancesthe fault tolerance of the EiP wave machine, and reduces manufacturingcosts.

2.2.4. Trapping and Concentrating Stray Rotor Flux

Peak axial flux linkage occurs at the moment of core saturation.Magnetic attraction between adjacent magnets produces a weaker magneticfield in both radial directions that traps radial flux at the rotoredge. Once the rotor is moving, leakage from fringing flux around thegap is swept up in this magnetic field by the C cores passing by, inphase with axial flux. Track curvature also creates a slight amount oftransverse flux. C core laminations of different length orientedperpendicular to the movement of magnets, concentrates this relativelysmall amount of transverse flux. All leakage flux components, radial,fringing, and transverse, combine in sync with axial flux on everycycle, eliminating rotor harmonics at the magnetic circuit level.Magnetic fields synchronous with magnet poles rotate with respect tostator cores. Each C core in the stator pair concentrates flux andcompletes the magnetic circuit with respect to magnet pairs, producingpure three-phase sinewave AC with no harmonics.

Unlike other large PM machines with distributed windings, stray rotormagnetic fields and harmonics are not an issue when PMLSMs are combinedbecause they connect at the DC link, with all AC componentselectronically filtered out. All rotor flux is concentrated at the PMLSMlevel, allowing the construction of a very large PM generator by addingmodules, unlimited in efficiency by induction of stray magnetic fields.

When motoring, switchmode electronic inverting produces a waveform thatis not purely sinusoidal. However, the aluminum rotor that holds themagnets is conductive, and a low-current non-sinusoidal potential existsbetween rotor and stator, which increases with speed. A contact (e.g.,brush contact) is required that dynamically connects to chassis groundduring all operations. The exemplary EiP wave machine uses two springmetal brushes mounted on copper attached to the inductor support frames,which remain in contact with the rotor at all times with low friction.This allows all non-sinusoidal motoring currents to follow the commonground path away from DC power output.

2.2.5. Exemplary Three-phase Magnetic Circuit

FIG. 2C shows a diagram illustrating an exemplary PMLSM three-phasemagnetic circuit of the present technology. The diagram of FIG. 2C showshow three adjacent stators connect as a wye to form one PMLSM, and howthey line up with axial rotor flux. The lower leg of each magneticcircuit is connected to a common point (C). Each upper leg of the wye(U, V, and W), attaches to EiP oscillator electronics (e.g., shown inSection 4).

2.3. Exemplary EiP Wave Machine Sizing and Expansion

EiP technology is naturally scalable to produce a very large interiorpermanent magnet generator. Self-similarity in structure at the modular,machine, and networked machine levels, supports a fractal pathway toexpansion. This section describes some example design rules for EiPmachine components, where a finite number of parts are replicated incertain patterns for expansion of EiP wave machine size and power. A keyaspect of EiP technology is cost minimizing by simplification: producingmore power from a small set of parts, replicated in specific ways tobuild the EiP wave machine. The most dramatic increase in power canoccur when the radius is expanded.

Described here are how the exemplary sizing of the inductor core andwindings is determined. Then, based on the optimum size of inductors andmagnets, overall machine size expansion is described.

2.3.1. Magnet and C Core Design

The selection of magnet dimensions affects the size of EM components,which determines electrical power for one PMLSM. The rotor radiusaffects the number of magnetic poles for a given size of magnet. A rotorcontains a certain number of magnets and layout, for example, for whichEiP technology specifies the following design rules.

1. Eight magnets per three C cores, above and below.

2. C core faces match the footprint of one magnet pair.

3. The length of core legs is at least three times the space between.

4. The space between magnets around the rotor circumference equalsmagnet width.

5. Magnet length equals three times the width.

6. Magnet thickness equals width (and thickness of the magnetic rotorplate).

7. Magnets are polarized through their thickness, arranged in oppositeaxial pairs.

For example, an exemplary EiP wave machine can be configured to have amagnetic track built using 160 NdFeB magnets. The magnet size is 2inches long polarized through ½ inch thickness, embedded around therotor separated by ½ inch. C core faces are 2 by ½ inch, with ½ inchbetween 1½ inch legs. The arrangement of magnets results in a rotordiameter of 55 inches, supporting enough inductors for 20 three-phasePMLSMs. Section 3 of this patent document provides more information onthe magnetic rotor physical characteristics.

For example, both magnets and C cores are commodity items, chosen forlower cost and optimal motor magnetics. The EiP magnetic design capturesand concentrates leakage and fringing flux that results from using lowcost magnetics, with optimum efficiency.

2.3.2. Inductor Core Windings and Fill Factor

The number of stator core windings can be determined by the absoluteamount of insulated copper wire that can be fit around C-core legs. Forexample, using mean length of turns (MLT) method for a given wire type,total inductance (and power) is determined by number of windings, thelength of each defined by core dimensions. Long wire length at a certainthickness offers higher DC resistance, which impedes magneto-motiveforce. To reduce these effects, a larger gauge wire must be chosen.Since the winding area is finite, the optimum number of windings dependson the fill factor: the relative amount of bare copper in the windingwindow divided by the window cross-sectional area.

In such implementations, for example, a fundamental design rule is toexpose the maximum amount of bare copper at any given instant to rotormagnetic fields. Each gauge and type of insulated motor wire offers acertain fill factor for a given core size. Using the cross-sectionalarea of the wire and insulation from its data sheet, divided into theavailable winding window area reveals how may half turns. Multiply theamount of bare copper in the wire cross-section by this number, anddivide that by the window area, for the fill factor. Calculating for arange of wire types and gauge, compare all the combinations and selectthe highest fill factor with the lowest DC resistance, and the maximumcorresponding number of turns. This guarantees maximum performance fromthe coil, for a certain size C core. FIG. 2D shows a diagram of anexemplary C core and fill factor. The diagram illustrates a crosssection of C core laminations and one coil, and the windingcross-sectional area.

For some exemplary embodiments of the EiP wave machine using 16-gaugewire, for example, the fill factor is 0.66 (⅔) for a total number ofwindings of 96 per C core leg. If 14-gauge square wire is used, the fillfactor is 0.85 with 60 turns per leg. The one with the highest fillfactor and lowest DC resistance (DCR), which exposes the maximum amountof copper to rotor magnetic fields, is best for generating. However, theone with the highest number of windings and lowest fill factor is bestfor motoring. Since EiP technology involves motoring and generating, theoptimum formula for a given core size may be found through testing ofthe two best designs. Table 2-1 shows the various combinations of wiresize that fit the exemplary C core legs, along with corresponding wireturns, fill factor, and total DCR.

TABLE 2-1 Wire Size and Fill Factor Combinations Wire Gauge and Type #Turns per Leg Fill Factor DCR #10  25 .70 .0294 Ω #12 Square  32 .72.0560 Ω #12  32 .56 .0672 Ω #14 Square *  60 .85  .150 Ω #14  60 .66 .166 Ω #16 **  96 .66  .404 Ω #18 148 .65  1.02 Ω #20 *** 205 .62  2.6Ω * Lowest DCR with highest fill factor. ** Highest winding number withlowest DCR. *** Maximum windings for best MMF using this example coresize.

2.3.2. Radial Expansion

The exemplary EiP wave machine optimizes the magnet and winding formulafor one C core size, for a modular structure that can be replicated fora larger radius of magnetic rotor.

The rotor is geometrically resized for more power, at certain incrementsthat fit installed modules. For much larger rotors, or otherapplications, like a wind machine rotor, or a powered propeller for aship, the optimal magnet/inductor size may differ.

Increasing the size of magnets and cores with machine radius is one wayto increase electromagnetic power. But, losses from eddy currents inlarger inductors present an upper limit to inductor size. Balancing allfactors produces a set of components for a PMLSM with optimum poweroutput. These smaller PMLSMs are replicated for radial expansionproviding the most dramatic increase in total power. Once a PMLSM sizehas been chosen, simply using a longer magnetic track that fits morePMLSMs (e.g., minimum 4 means adding 32 magnets), expands the size andpower of an EiP machine. This technique allows the creation of verylarge radius rotors. For magnet and inductor sizing used in theexemplary embodiment of the EiP wave machine, every integer multiple of32 magnets expands the rotor radius by approximately five inches,accommodating four additional PMLSMs. The pole pitch remains constantfor each configuration. Using this technique, EM torque matches orexceeds mechanical torque as the radius expands, along with moremagnetic poles to maintain synchronous operation at slower speed. FIG.2E shows a diagram of an exemplary magnetic rotor expansion usingidentical magnets and pole pitch. The diagram illustrates magnetic rotorexpansion, for additional 32 magnets of the size.

2.4. EiP Oscillation

The EiP oscillation is self-sustaining, representing all of combinedelectrical and kinetic energy in an EiP machine, where rotor speed andDC link voltage periodically rise and fall to maintain power balance. Asrotor speed increases, either from reduced load or high airflow, totalenergy potential increases. As the rotor decelerates under load, it ishyper-sensitized to sudden changes in airflow speed that bolster energyuptake. When total energy is greater than load, rotor speed moves up anddown under EiP oscillation, at fixed DC link voltage. EiP oscillationalso applies to spontaneous networks of EiP wave machines, when storingand sharing power on the grid.

2.4.1. Van Der Pol Model

The EiP oscillation follows the Van Der Pol Model, where a parasiticoscillation draws in energy from the system in which it occurs. The VanDer Pol model is characterized by the following differential equation,Equation 2-2, which represents the Van Der Pol Differential Equation:

x″+x=ϵ(1−x ²)x′ for ϵ>0  (Eq. 2-2)

Equation 2-2 produces one periodic solution: a relaxation oscillationwith a stable limit cycle. In the disclosed EiP technology, x representsa continuous function for EiP machine power, and c corresponds to theperiod of oscillation. The period is locked to harmonics of rotor speed:at a dead stop, x equals zero and E is infinite. As rotor speedincreases, x increases while decreases (but always >>one). When thenon-linear term ϵ(1−x²)x′ reaches the singularity where the periodicsolution to the equation is found (for a given ϵ), an oscillation with astable limit cycle occurs. The limit cycle is attracting toward thesingularity, in this case drawing energy from the system in which itoccurs. At rotor operating speeds (larger ϵ) the single periodicsolution to the Van Der Pol equation describes a relaxation oscillationthat quickly jumps from a smooth curve to another and back again, asdepicted in FIG. 2F.

FIG. 2F shows a plot of Van Der Pol oscillation limit cycle. The plotshows the attractor for oscillation limit cycle, where the dot 280follows the wide arrows 281 from the smooth curved part to the peak thenquickly across to the start of a new half cycle. The thin arrows 282indicate the proportions of energy drawn from the system in which theoscillation occurs.

2.4.2. Relaxation Oscillation Period

The Van Der Pol oscillation period T can be broken down into two parts:smooth and quick, as shown in the following equation, Equation 2-3,which represents the Van Der Pol Oscillation Period:

T=(3−2 log2)ϵ+η(ϵ^(−1/3))  (Eq. 2-3)

Smooth+Quick

In the disclosed EiP technology, for example, the smooth part representsenergy from airflow and inertia, while the quick part represents powerinjected to maintain rotor speed. The period is locked to a harmonic ofrotor magnetic transition speed. Since total energy is a function oftime, the relative amount of injected power required is very smallwithin a single cycle (e.g., linear log function vs. negative cubicexponential function). EiP technology maintains this relationship overthe full range of rotor speeds (e.g., smaller ϵ), where a greaterportion of the oscillation period is powered by inertia as rotationspeed increases.

2.4.3. Negative Resistance Oscillator

For example, the Van Der Pol model was developed by observing theoscillations from an electronic circuit for the negative resistanceoscillator, as shown in the diagram of FIG. 2G. FIG. 2G shows a diagramof an exemplary negative resistance oscillator of the presenttechnology. This exemplary circuit oscillates at a specific frequencybased on L and C. At this frequency, the oscillation is self-sustainingand attracting. In the negative resistance oscillator, E₀ from thetunnel diode is drawn along with I₀ from the battery supply to power theoscillation. The capacitor and inductor store enough energy to power thequick part of the oscillation period.

2.4.4. EiP Oscillator

The minimum amount of circuitry required for an EiP oscillator may bemore complex. The EiP wave machine is wired to produce necessary DCvoltage using identical stator inductors. The output of three-phaserectifier circuits are stacked in series, with each one producing DCequivalent to peak AC voltage with small amount of ripple at 6×ACfrequency plus non-sinusoidal currents. Motoring stators are powered bya fraction of output voltage which is fed back to the DC bus of a VSC.Intelligent control of the VSC is done by analyzing ripple currents andperforming rotor flux estimation techniques. EiP oscillation occurs whengenerating stators sustain motoring stators, while the rotor is poweredby direct torque control. FIG. 2H shows a pseudo-schematic of anexemplary minimal EiP oscillator, where power from a minimum number ofgenerating stators connect with motoring stators.

The drawing of FIG. 2H shows a minimum number of generating PMLSMs withrectifiers, enough to support the DC link for the voltage sourcedconverter (VSC) circuit in the motoring PMLSM. Rotor magnetic fieldspass through the generator phases, at a certain speed the DC linkvoltage is always higher than required by the motoring VSC. The EiPoscillation sustains the DC link, with net zero torque, along with asubstantial amount of kinetic energy from accumulated rotor inertia.Change in rotor speed represents energy potential equal to theelectrical load offset by wave energy uptake. During EiP oscillation,periodic fluctuation in rotor speed at constant DC link voltage powersall connected loads along with the oscillation, drawing in energy frominertia, in a similar way to the Van Der Pol model. EiP oscillationcontinues indefinitely until rotor speed drops below a certainthreshold, where external power can be introduced to sustain oscillationif the EiP machine is networked with others.

The exemplary EiP architecture is flexible and adaptable to a widevariety of large radius electrical machines, from motors to generators.For example, EiP oscillator modules can be stacked where the totalnumber of stators is divided into motoring and generating groupsdepending on what the application requires. The EiP wave machine can beoperated strictly as a generator, which is able to produce maximumvoltage for long wire runs to shore. So, only one PMSLM is used formotoring inertia control, for example, while all others are stacked formaximum DC voltage from a given radius machine. The EiP oscillator andVSC architecture as applied to the exemplary EiP wave machine aredescribed in further detail in Section 4.

2.5. EiP Operating Modes

The disclosed technology includes three operating modes: coasting,motoring, or generating. Diode rectifier bridges attached to each statorproduce a DC voltage that increases with rotor speed: with no loadattached, the “coasting” operating mode. Parallel transistor switchescontrol the rectifier as a VSC, to produce positive torque that speedsup the rotor: “motoring” mode. Negative electromagnetic torque fromelectrical loading slows the rotor: “generating” mode. A fourthoperating mode is defined when parallel PMLSMs are motoring andgenerating: “oscillating” mode. EiP technology includes these operatingmodes to provide software a feedback mechanism for networking andfine-tuning of the system, as summarized in Table 2-2.

TABLE 2-2 EiP PMLSM Operating Modes Mode Definition Indication 0Coasting Voltage rises with rotor speed until motoring or generating. 1Motoring High instantaneous torque power for startup and speedregulation. 2 Generating Power production when electrical loads producenegative torque. 3 Oscillating One PMLSM motoring while two or more aregenerating, creating the conditions for EiP oscillation.

2.5.1. EiP Mode Control

Each motoring PMLSM operates from a set of parameters, some for control,others for status. A central controller device globally initializesmotor parameters on startup, then monitors status parameters todetermine the operating mode. Running autonomously, and in parallel,PMLSM electronic control happens much faster than air speed and loadchanges, so there is ample time to monitor operating modes and fine-tuneparameters. Under heavy loading and higher rotor speed, for example, allPMLSMs are in generator mode, and slow the rotor. Under reduced load andabsence of airflow, one PMLSM may switch to motoring to keep up rotorspeed while another is generating. When an individual PMLSM controllerencounters an exception to parameter settings, like rotor overspeed withno load, it will coast until normal limits are restored.

At a certain point, the balance of power lets EiP oscillation takecontrol. The random interactions of all installed PMLSMs allow the EiPoscillation to naturally arise from chaotic and turbulent operatingconditions, like any non-linear phenomenon. Once oscillating, the EiPmachine has greater power potential, backed by the natural behaviors ofparasitic oscillation described above.

To configure the EiP wave machine for greater power uptake, for example,more PMLSMs are dedicated to motoring. For installations with greaterairflow availability, only one PMLSM is used for motoring, while allothers are dedicated to generating.

All motoring PMLSMs in an EiP wave machine can share a common networkhardware connection, like RS485, for parameter configuration andmonitoring. Remote monitoring software receives packets of data, withthe operating mode as header along with other real-time information,e.g., voltage, current, temperature, etc. Over time, the configurationis fine tuned to obtain maximum energy from the installed location,using EiP operating mode packets.

2.5.2. Networked EiP Wave machine Operating Modes

In an EiP wave machine spontaneous network, operating mode/statuspackets provide a way to synch up with other machines on a common gridsegment. The EiP operating mode has a fractal quality, withself-similarity at the module, machine, and network levels. On thenetwork, EiP modes indicate the following:

-   -   Mode 0—Coasting, or offline.    -   Mode 1—Motoring, accepting incoming grid power.    -   Mode 2—Generating, providing power for the grid.    -   Mode 3—Oscillating, indicating surplus stored power.        For more information refer to the “System Architecture” and        “Programming” sections of this patent document.

2.5.3. PMLSM Motor Parameters

Each PMLSM can be controlled like a rotary three-phase machine in afactory environment. For example, manufacturers of three-phase drivesdefine a set of parameters for fine-tuning of machine operations. Thefirst three parameters are determined from the size of inductors, withvalues calculated using coil formulas or by direct measurement. Themotor nameplate frequency represents the nominal synchronous AC inputfrequency. PM pole pitch is the distance between pole pairs in themagnetic track. The motor force constant and PM flux linkage arecalculated using the equations in the “Power Calculations” section(Section 2.6).

2.5.4. Energy Balance Through Simple Speed and Voltage Regulation

Once up and spinning, the DC link voltage reaches a level whereautonomous voltage and speed regulation in the motoring PMLSM takeshold. Rotor speed is regulated by the PMLSM, using forward and reversemotoring operations. Electrical loading of the DC link and airflowuptake occurs at random moments, while motoring torque regulates rotorspeed, to maintain the DC link voltage as shown in FIG. 2I. FIG. 2Ishows an exemplary diagram depicting the essential EiP energy imbalance.

The disclosed EiP technology actively manages the differential imbalancebetween wave energy uptake, inertia, and load, through quick motoringoperations in response. As rotor speed increases from wave energy uptakeand/or forward motoring, excess energy from inertia (overhauling) buildsup to a point where greater loading is required to lower the DC linkvoltage. PMLSM motoring maintains rotor speed (and inertia) whilelowering the DC link voltage. Electrical loading on the DC link dropsthe voltage and decreases rotor speed, while high inertia tends to keepthe rotor at speed. PMLSM regulation operations provide instant thrustforce in both directions, managing rotor movement to keep the DC link ata constant level while delivering power to loads. When inertia plus waveenergy is greater than electrical loading, DC link voltage can no longerbe maintained, and the essential imbalance becomes chaotic, allowing theEiP oscillation to naturally manifest as periodic rotor speed and/or DClink voltage fluctuations.

2.6. Power Calculations

This section provides equations for determining total power of an EiPwave machine: from inertial, electromagnetic, and wave sources.

2.6.1. Rotational Inertia

The exemplary EiP machine magnetic rotor can include a flywheel wherethe stored energy equals the sum of kinetic energy of individual masselements, which can be calculated using the following equation, Equation2-4: Magnetic Rotor Kinetic Energy Equation:

KE_(R)=½I_(R ω)) ²  (Eq. 2-4)

where: I_(R)=Magnetic rotor moment of inertia, which is the ability toresist changes in rotational velocity, in this case, to maintain rotorspeed under sudden changes in electrical loading; and where:ω=Rotational velocity (rpm) of the rotor.

The magnetic rotor element is basically a hollow cylinder of uniformdensity with thick walls, for which the moment of inertia can becalculated using the following equation, Equation 2-5: Magnetic RotorMoment of Inertia Equation:

I _(R)=½m(r ₁ ² +r ₁ ²)  (Eq. 2-5)

where: m=Rotor mass in Kg; r₁=Inner rotor radius; and r₂=Outer rotorradius.

However, the magnetic rotor element is actually formed in three layers,one of which is of different density. For a precise determination of themoment of inertia from the density of materials, use the followingequation, Equation 2-6: Magnetic Rotor Layer Moment of Inertia Equation:

I _(L)=½πρh(r ₂ ⁴ −r ₁ ⁴)  (Eq. 2-6)

where: ρ=Rotor layer material density in Kg/m³; and h=Rotor layerthickness in meters.

The entire rotor inertia is the sum of the inertias for each layer, plusinstantaneous airflow force. Note that as the radius increases, inertiaexponentially increases. Traditional flywheels for energy storage andproduction operate using a small radius with low moment of inertia thatspins at extreme speeds. Unlike high-speed flywheels, the EiP machineleverages a large radius and high moment of inertia, which operates onlyslow speed. In both cases, total energy storage increases with thesquare of angular velocity. In the EiP flywheel, high inertia means thateven though it spins slowly, peak power output is naturally enhancedalthough storage time is less. EiP technology leverages instant powerfrom high inertia for increased total energy storage through electronicoscillation.

2.6.2. Inertial Power in EiP Oscillation

Power from inertia builds up as rotor speed increases. The speed changerepresents a certain amount of power, as shown in the followingequation, Equation 2-7: Total Inertial Power Equation:

W=I _(R)(Δrpm 2π/60)²  (Eq. 2-7)

where: W=Power in Watt-seconds; I_(R)=Rotor inertia in Kgm²; andΔrpm=change in angular velocity, as the rotor slows down under load orincreases with airflow energy uptake.

The power recovered from inertia is equal to the downward change inrotor speed under electrical load. If the rotor is allowed to slow allthe way down, the total power capacity in the rotor is recovered. In theEiP wave machine, the speed is allowed to oscillate up and down,constantly storing and withdrawing inertial power to maintain DC linkvoltage. As wave energy and electrical loads fluctuate wildly, the rotorslowly speeds up and slows down at a frequency determined by parametersettings for each installed PMLSL. The EiP oscillation amplitude (peakpower) corresponds to twice Δrpm, representing the power in bothdirections.

2.6.3. Energy Stored In Magnetic Fields

Electromagnetic power in the EiP machine comes from rotor magneticfields, concentrated by C cores through an air gap, which abruptly passthrough copper windings, freeing electrons and inducing current in thecoil. As the speed of flux transitions increases, the greater thecurrent density. From the permanent magnets embedded in the rotor, thelines of flux do not weaken over time because of the large amount energythat creates them, as shown by the following equation, Equation 2-8:Magnetic Field Power Equation:

W _(v) =B ²/2μ  (Eq. 2-8)

where: W_(v)=Power stored in magnetic flux; μ=Permeability of themagnetic gap and C core; and B=Flux density of one rotor magnet.

For example, for each rotor magnet, the flux density of NdFeB and highpermeability C core produce high energy magnetic fields. Multiplied bythe number of magnets in the rotor, total flux reveals a tremendousamount of energy potential, which explains why motoring PMLSMs produce alarge electromagnetic torque response from a relatively small input.

2.6.4. Electromagnetic Power and Torque

The mathematical model of each PMLSM is based on equations describingstator voltage, flux linkage, power, and thrust force (torque). EachPMLSM is treated like a rotating four-pole three-phase synchronousmachine. The electromagnetic torque and flux linkage of each PMLSM addsup for total power. The model follows the direct-quadrature (d-q) axisconvention, using rotor magnetic fields as the rotating frame ofreference. When using the d-q frame, the model becomes much simpler, andstandard DTC techniques for a rotating machine work perfectly with thelinear implementation. Essentially the d-q frame represents theconversion of three phases to two, using only simple equations for fluxlinkage vs. magnetic frequency.

2.6.4.1. Stator Voltage Calculations

Total power from an EiP machine is the sum the power for each PMLSM.Unregulated stator voltage increases with rotor speed along with totalpower, calculated using the following equations, Equation 2-9: d-q FrameStator Voltage Equations:

u _(d)(t)=Ri _(d) +dΨ _(d) /dt−ωΨ _(q)

u _(q)(t)=Ri _(q) +dΨ _(q) /dt−ωΨ _(d)

P _(in)=3/2(u _(d) i _(d) +u _(d) i _(d))  (Eq. 2-9)

where R is the wire resistance of stator windings, i_(n) is the statorcurrent vector, ω is the AC frequency, and Ψ_(n) is the flux linkagevector.

2.6.4.2. Flux Linkage Calculations

Power is transferred between mechanical and electrical domains byinterlocked lines of magnetic flux from permanent magnets and copperinductors wrapped around magnetic steel. Flux linkage on d and q axes iscalculated using the following equations of Equation 2-10: d-q frameFlux Linkage Equation:

Ψ_(d) =L _(d) i _(d)+Ψ_(PM)

Ψ_(q)=L_(q)i_(q)  (Eq. 2-10)

where L_(n) is the stator inductance and _(W)PM is the permanent magnetflux linkage.

2.6.4.3. Electromagnetic Power and Thrust Force Calculations

EM power represents how much power the EiP machine can generate inresponse to mechanical power from the rotor. Thrust force is the linearequivalent of instantaneous torque in a rotating machine. From the fluxlinkage and stator voltage values, EM power and thrust force can becalculated for each PMLSM using the following equations, Equation 2-11:Three-phase Power and Thrust Equations.

PEM=3/2 ω[Ψ_(PM)+(L _(d) −L _(q))i _(d) ]i _(q)

P _(Thrust)=3/2 π/96 [Ψ_(PM)+(L _(d) −L _(q))i _(d) ]i _(q)  (Eq. 2-11)

where τ is the PM pole pitch, which is the physical distance betweenpairs of axially polarized permanent magnets on the magnetic track. Inthe EiP machine PMLSMs operate in sync with each other around the rotorto form one large machine with the sum of power and thrust.

2.6.5. Mechanical vs. Electromagnetic Torque

On the standard Wells turbine, the central shaft restricts instantaneoustorque applied to the generator as the rotor radius is increased; only afraction of total torque is allowed before twisting or breaking theshaft. In the EiP wave machine, mechanical torque is unlimited by acentral shaft, so the transformation to electromagnetic torque is one toone. This means that all rotor torque (T_(Rotor)) has an electromagneticequivalent, where positive mechanical torque from rotor thrust force isoffset by negative electromagnetic torque from PMLSM thrust force. Thefollowing equations, Equations 2-12 Wind vs. Three-phase Thrust ForceEquations, which show the thrust force that can be generated by therotor and PMLSM with respect to Wells turbine performance coefficientsfor pressure (Ψ), torque (π), and efficiency (η):

Ψ=Δp/ρω ² r ²

π=T _(Rotor)/ρω² r ⁵

η=T _(Rotor) ω/Δp Q  (Eq. 2-12)

where: ρ=density of air; ω=rotor speed; r=rotor radius; andT_(Rotor)=rotor mechanical torque.

Note that when performance coefficients are calculated for a given Wellsrotor radius, T_(Rotor) increases dramatically with turbine size, to apoint where EiP technology is required to provide electromagnetic torquefor rotor speed control.

F _(3-phase Thrust)=3/2 π/τ[Ψ_(PM)+(L _(d) −L _(q))i _(d) ]i _(q)  (Eq.2-13)

where: Tτ is the PM pole pitch; L_(n) is the stator inductance; Ψ_(PM)is permanent magnet flux linkage; and i_(n) is the stator current.

PMLSM thrust force, multiplied by the rotor radius r, defines the torqueresponse which is directly converted to power in balance with T_(Rotor).

3. Mechanical Specification

The mechanical design for the exemplary EiP wave machine includesfeatures and principles including, for example, strength, faulttolerance and reliability in an ocean environment; buildable designusing basic fabrication techniques and common raw materials; and amodular and expandable design supporting quick field service andupgrades.

Examples are described and diagrams are shown based on specifications ofsome exemplary embodiments, e.g., representing a small or minimum sizeof an exemplary EiP wave machine, which is readily expandable to muchgreater size and power.

3.1. Mechanical Overview

The exemplary EiP wave machine described in this section includes twomechanical parts: one moving and one stationary. The moving part is therotor, which can include an integrated Wells turbine hub and bladeassembly, high inertia flywheel, and magnetic rotor containing multipleoppositely polarized magnets (e.g., NdFeB bar magnets) laid out as amagnetic track near the outer flywheel circumference. The stationarypart can include a housing for rotor bearings, stationary inductors, andelectronics.

In some implementations, the exemplary EiP wave machine can beconstructed in two halves. Each half provides a housing for afield-serviceable bearing support for one side of the flywheel, and onehalf stator array with electronics and wiring. The rotor/flywheelassembly can be inserted into one assembled half, with non magneticshims inserted between magnets and inductors to maintain the proper gap.The other half is installed with shims and both halves are secured.Shims are removed and the two halves are “strapped” together.

3.2. Exemplary EiP Machine Mechanical Design

This section describes each part of the exemplary EiP wave machine. Themechanics integrate a Wells turbine rotor and high-inertia flywheel withpower generation in a unique design, using only one moving part.Stainless steel rings position stator pairs on each side of the magneticrotor, and roller bearings guide and support the flywheel edges. Forexample, the EiP wave machine has no drive shaft. The hollow centerprovides a clear path for airflow to exit the turbine, for greaterpneumatic power efficiency. A fault-tolerant mechanical designeliminates the centralized generator shaft and main bearing. FIG. 3Ashows a cross sectional diagram of an electronic inertial powergeneration unit 310 of an exemplary EiP wave machine, with some of thesame or similar features as that shown in FIG. 1B. For example, theelectronic inertial power generation unit 310 includes a set of verticalbearings 103 coupled to the side plate of the bearing-ring track 313 anda set of side rollers or bearings 303 that protrude through a hole inthe side plate of the bearing-ring track 313, in which the bearing-ringtrack is mounted to the support base of the frame 111, e.g., by bracketson an opposite side to secure the bearing shaft.

The following description describes some example specifications ofsubassemblies, e.g., each appearing under its own subheading: rotor andflywheel, inductor rings, housing, and bearing rings.

3.2.1. Rotor/Flywheel Assembly

FIG. 3B shows an axial view diagram depicting the exemplary magneticrotor, high-inertia flywheel, and Wells rotor of an exemplary EiP wavemachine.

The magnetic rotor can be configured as an annulus of magnet thickness,which protrudes from the flywheel, providing an array of permanentmagnets around the outer circumference. In some embodiments, forexample, neodymium iron boron magnets, of alternating axial polarity,are attached (e.g., can be glued) in place around the magnetic rotor(e.g., using high peel strength epoxy). The array of magnets of themagnetic rotor concentrate axial flux above and below the rotor, whileproducing minimal radial flux.

In some embodiments, for example, the high inertia flywheel is formed bytwo thick-walled cylinders made of high density material, with in innerpart of the magnetic rotor annulus sandwiched in between. This forms asource of inertia for the rotor, to steady rotor speed in an oscillatingairflow. For example, the high density material of the flywheel halvescan include cast epoxy resin, or an aluminum casting. In someimplementations, for example, flywheel halves could also be made of castconcrete. In some implementations, for example, it is also possible tofabricate the flywheel in layers of cut sheet metal of a certainthickness like ½″ stainless steel, stacked and bolted together to form ahollow cylinder. The common property is that the high density materialshould be non-magnetic. The absolute density of material depends on thesize of the machine, and what the desired moment of inertia should be.

A Wells-type rotor is attached to the inner radius of the flywheel. Insome embodiments, for example, the Wells-type rotor includes a hub withsymmetrical airfoils (e.g., NACA 0020) attached, with chord linesparallel to the axis of rotation. It can be of a high solidity designwith the inner surface of the flywheel providing endplates for theblades, for maximum pneumatic efficiency.

In contrast, for example, a standard Wells turbine has the hub support acentral shaft that drives an inline generator. A nose cone is added toreduce turbulent flows that reduce efficiency. In the disclosed EiP wavemachine technology, the hub is a simple disk of greater thickness thanrotor blades. Since there is no shaft or generator, air friction on therotating surface of the flywheel and hub eliminate turbulence on inflow.Outflow is enhanced because the center is open behind the hub, allowingturbulent flows on the backside of the rotor blades to coalesce into awake vortex, creating a greater pressure drop between input and output.

In implementations, for example, as the rotor spins, lines of fluxrotate like a spinning motor armature, which produces alternatingcurrent on series connected stator coils on either side of the magneticrotor. Since the magnetic array operates at the rotor edge, the magneticfrequency is maximized for a given rotor radius. Voltage increases withflux transition speed, and the AC waveform is sinusoidal, hallmarks of asynchronous machine. Multiple stator pairs instantly derive excitationfrom rotating magnetic fields in parallel, which is rectified to DC andwired in series for maximum voltage. One module is dedicated to providemotoring thrust force applied to the entire radius for maximum torque inrotor speed regulation operations. FIG. 3C shows a diagram of an examplerotor assembly, depicting a 60 degree section of the magnetic array anda cross section of the Wells-type rotor, magnetic rotor, and flywheel.

For example, the hub, blades, and magnetic rotor can be configured as asingle machined aluminum casting, with holes for magnets and high peelstrength epoxy. Magnets are positioned as shown in the diagram of FIG.3C. Dimensions shown between arrows are: m equals magnet thickness whichdefines the size of inductors, b equals blade thickness which determinesinstantaneous rotor power, h equals rotor hub thickness which can begreater than blade thickness. L and t determine rotor inertia, where tequals outer flywheel radius minus the inner radius which increasesinertia exponentially, L is the flywheel length which multipliesinertia. The flywheel can be made in two half cylinders of high densitymaterial like steel with the magnetic rotor sandwiched in between, toform a single rotating mass.

3.2.2. Housing

The non-rotating part of the exemplary EiP wave machine can be built intwo halves, connected by a sealed watertight cover that straps the twohalves together to precisely determine the gap between magnetic rotorand stators. Each houses one half of the inductor array pluselectronics, and rotor bearings. A set of threaded holes are providedthat fits a standard pipe flange bolt pattern. The exemplary embodimentdiscussed in Section 3 conforms to the ANSI Class 150 DN1200 48″ pipeflange. A bearing ring assembly is attached inside the flanged end, theinductor ring is bolted onto the other. A hollow chamber is formedbehind the installed inductor ring for wiring and electronics. FIGS. 3Dand 3E show diagrams showing one half-housing front view of the frame111 with pipe flange holes 119 and rear view showing inductor ringmounting holes. FIG. 3D shows a diagram showing a front view andcross-section of an exemplary half of the housing. FIG. 3E shows adiagram showing a rear view of an exemplary half of the housing.

Each housing half can be a machined aluminum casting with walls of aminimum thickness on one end, around a cavity for internal wiring andelectronics. The walls contain threaded holes for inductor ringmounting. One half supports electronic circuit boards and rectifiermodules, the other supports HVDC power leads and fiber optic networkinterface connecting with electronics. Wall thickness increases withmachine size while the cavity size remains constant, corresponding tothe size of inductors. When the radius expands more inductors andelectronic modules are added around the cavity, which roughly remainsconstant in width with respect to machine radius expansion. Wallthickness must be great enough to support dramatic increase inmechanical inertia with radius, along with corresponding amounts ofelectromagnetic torque response, e.g., in the same manner as expandingANSI standard pipe and flange thickness to larger diameter.

3.2.3. Inductor Rings

In some embodiments, for example, two circular stainless steelU-channels support an array of inductors, one for each side of themagnetic rotor array. A circular base plate can be laser cut, withcurved steel plate welded around inner and outer edges. Holes areprovided for inductor sites, along with wiring pass-through holes toelectronic mounted on the opposite side. Holes are also provided formounting to the housing, as shown in the diagram of FIG. 3F which showsthe inductor side view of the assembly. FIG. 3F shows a diagram of anexemplary EiP wave machine inductor support ring.

3.2.3.1. Inductor Mechanical Specification

Each inductor in the exemplary EiP machine can be encapsulated in epoxy,to hold the C core in place under strong magnetic forces, and protectwindings from harsh environmental conditions. Four threaded insertssupported by “L” brackets in epoxy provide mounting hardware. FIG. 3Gshows diagrams depicting example inductor specifications, and how it canbe constructed. As shown in FIG. 3G, the graphic 371 shows the outlineof the epoxy potting for a pair of inductors, with dotted linesindicating the locations interior parts, and a direct side view of whatis inside (e.g., brackets for threaded inserts, C core, and wire leads).The graphic 372 shows the C core and winding area as viewed from themagnet side (core faces), and from the opposite side showing thefootprint of the mounting brackets and threaded inserts. It is noted,for example, that the dimensions are all in inches. The graphic 373shows a cross section of the C core and winding area as viewed from therotor edge.

Epoxy encapsulation protects the C core and windings from harshenvironmental conditions. The EiP machine frame, supporting bearings andinductors, provides drain holes and open vents allow water to quicklyenter and exit the inductor operating environment. High-density axialflux lines quickly saturate the C core when pole faces line up, so themagnetic rotor gap need not be too tight. Wiring for the inductorspasses through a hole into a sealed compartment around the pipe flange,that contains electronics and wiring. All electrical connections aresealed from the elements in accordance with codes and standards forsubmersible use.

In the exemplary EiP wave machine, there is a lot of discretion as tohow long the C core legs can be configured, e.g., which increases thewinding area without affecting the mounting or magnet patterns. Forexample, by lengthening the core, one can increase the working voltageby adding more windings, and reduce the added resistance (increasepower) by using thicker wire, all of which can be accommodated by theincreased winding area. Yet, for example, a larger core may lead toincreased eddy current losses, and so one may have to increase thedoping of the magnetic steel laminates in the core from 3% silicon to ahigher value, e.g., like 4 or 5%.

3.2.4. Bearing Rings

Instead of a single bearing controlling a shaft, for example, the EiPwave machine can provide an array of roller bearings that restrict rotorflywheel motion on two axes, such as that shown in FIG. 3A. One set ofbearings supports the full weight in rotation, e.g., the verticalsupport bearings 103, and the other controls side to side motion whichmaintains proper magnetic gap alignment, e.g., side roller bearings 303.A cover over the bearing ring can be included to create a venturi, e.g.,reducing the 1200 mm pipe flange opening to 1000 mm on input and outputin this exemplary embodiment of the EiP wave machine. FIG. 3H shows adiagram depicting an exemplary bearing ring as viewed from the flywheel.

In case of a bearing failure, high redundancy takes over the load untilscheduled maintenance. Then, the ring cover is removed to exposefasteners into the flange end of the housing for removing the entirering so that bearings can be easily replaced during field service.Maintenance-free poly roller bearings provide quiet operation underheavy load. These bearings are available from a wide variety of OEMsources, in a variety of sizes, for example. Roller diameters for sidebearings determine the magnetic gap between the magnetic rotor andinductors, balanced to fit equally between the inductor rings. Flywheelsupport bearings are sized for low eccentricity rotation of the magneticrotor with respect to inductors.

The main roller bearings can be bolted into threaded inserts. The siderollers can be configured to protrude through a laser cut hole in thebearing plate, with custom brackets on the opposite side to secure thebearing shaft. FIG. 3I shows a diagram showing a closer view of theexemplary bearings 103 and 303 and how they attach to the bearing ring113.

3.2.5. Strap

In some implementations of the EiP wave machine, the machine includes awatertight cover strap that is attachable/detachable to the openings ofthe base support, and that can be completely sealed to prevent fluidfrom leaking within. The term “strap” represents a watertight cover thatprovides the mechanical support required to connect each half housingduring final assembly. The strap must solidly hold the machine togetherusing structural components and fasteners appropriate for the size ofmachine. The strap also provides lift points for hoisting the EiP wavemachine during installation, without grabbing the flange ends. The exactstructure of the strap depends on machine size, for example, sincemechanical forces that affect structural integrity increaseexponentially with radius.

4. Electronics Hardware Specification

The disclosed technology is modular at the electrical machine level bybreaking down a large array of stators and rectifier electronics intothree-phase groups: permanent magnet linear synchronous machines(PMLSMs). Each PMLSM has an integrated three-phase rectifier module,which converts AC to a DC at peak AC voltage. Stators connect in a wyeconfiguration, with each leg electrically isolated from the DCinterface, post rectifier. Three or more PMLSMs can be combined asbuilding blocks to create certain configurations of EiP machine. OnePMLSM provides a Voltage Sourced Converter (VSC) circuit for motoringand generating, while all others provide simple three-phase dioderectifiers for generating only. For high voltage DC output, generatingrectifier DC outputs are wired in series. A DC-DC converter is connectedto the HVDC output to provide feedback the DC link, creating an EiPoscillator.

4.1. Three Phase Diode Bridge Rectifier

The primary linear electronic building block for a generating PMLSM is asimple six-segment three-phase diode bridge rectifier, as shown in theexample of FIG. 4A. FIG. 4A shows a circuit diagram depicting anexemplary PMLSM diode bridge. Diode bridges are stacked in series orparallel for a certain voltage/current configuration on the DC link.Each leg of the wye is an EiP synchronous magnetic circuit, designed towork with industry-standard three-phase rectifier modules.

Stator AC is only allowed to flow in one direction, so when the three ACwaveforms are superimposed, it results in roughly a DC voltage thatequals peak AC voltage. Ripple is low enough to eliminate the need forfilter capacitors. Parallel connections allow one or two stators to failwith continued operation but at a lower voltage with higher ripple.Series or parallel connected modules are unaffected by individualinductor or diode failures.

4.2. Voltage Sourced Converter (VSC)

For motoring modules, an industry-standard three-phase module called avoltage sourced converter (VSC) is required. The VSC circuit placessemiconductor valves like the insulated gate bipolar transistor (IGBT)in parallel with each diode in a three-phase rectifier, to become acontrolled rectifier/inverter. In a three-phase group, packaged forindustrial use, the circuit is commonly called a variable frequencydrive (VFD). IGBTs are controlled by pulse width modulation (PWM) ofgate signals for motoring and generating operating modes, turningvariable voltage and frequency three-phase AC power into a fixed DC linkvoltage when generating, or inverting DC link power to three-phase ACpower of variable voltage and frequency for motoring. When the IGBTs areinactive, the rotor simply coasts and the circuit reverts to athree-phase rectifier. FIG. 4B shows a schematic diagram showing theexemplary VSC and PMLSM stators.

PWM-controlled IGBTs provide power factor and phase control for eachstator leg. PWMs are provided by an intelligent controller part, whichgenerates waveforms on the IGBT gates that regulate the flow of currentthrough IGBTs. Software control of the rectifier uses rotor fluxestimation techniques based on real-time analysis of ripple currents onthe DC side by a digital signal processor. All timing and feedback isderived from rotor flux/stator estimations, e.g., eliminating outboardspeed sensors.

VSC controller electronics are powered by a separate low-voltage supply,which is easily battery-backed. When the supply is removed, all IGBTs goto a high impedance state, and the circuit becomes a simple passiverectifier. Diodes completely isolate stators in the reverse directionfrom the DC link voltage. This removes the threat of cascading breakdownif a fault occurs, where a diode becomes an open circuit if current istoo high, and the stator leg is completely cut out of the circuit.

4.2.1. Power Factor Control

PWM control of IGBT gates adjusts the power angle between reactive andresistive parts of stator interactions with the magnetic rotor,providing power factor control. The PWM controller monitors AC frequencyusing sensorless techniques, for rotor speed indication. Rotor speedcorresponds to total power potential speed regulation defines powerlimits.

4.2.2. Power Regulation Through Motoring

Airflow from wave energy uptake accelerates the rotor, which raises theDC link voltage. Electrical loading on the DC link decelerates the rotorand lowers DC link voltage. Each PMLSM with VSC regulates speed byforward and reverse motoring using integrated PWM control. When rotorinertia is high, braking by reverse motoring (generating) causes DC linkto rise. Forward motoring causes DC link to drop (by loading) whilerotor accelerates. When motoring and generating, the rotor speeds up andslows down while DC voltage remains constant. At maximum rotor speed,the DC voltage is allowed to fluctuate.

4.2.3. High Frequency PWM Support

The PWM carrier frequency is thousands of times greater than generatorfrequency. In the EiP machine, for example, smaller silicon steel Ccores allow maximization of PWM frequency, for high speed and higherresolution control. If a high frequency is chosen, for example 16 KHz,switching harmonics can produce eddy current losses in large monolithiccores. Discrete core segments, built with 3% silicon steel laminates,naturally operate at higher frequencies with low losses, so PWMfrequency is maximized.

4.2.4. Off-the-shelf Industry Standard Variable Frequency DriveCompatibility

VSC technology is fairly mature, where a variety of modular industrialVFDs are available from various manufacturers off-the-shelf, andprogrammed to fit PMLSM motor parameters. EiP technology can use thestandard VFD as the electronics hardware platform. For example, in someembodiments of the EiP wave machine, the machine can be fabricated forfaster time-to-market, in which the machine contains one off-the-shelfVSC for a motoring PMLSM, while all others use diode bridges. A grid-tieinverter connected to the DC link creates an EiP wave machine gridinterface that conforms to standards.

In some embodiments of the EiP wave machine, custom VSCs are integratedinto every PMLSM in the wave machine frame, with built incycloconversion for direct grid-compatible AC.

4.2.5. Electronic Mechanical Compensation

High-speed electronic control of instantaneous PMLSM thrust force allowstight control of large and loose mechanical systems. The EiP wavemachine is subject to random mechanical forces from airflow andmagnetics that cause undesirable vibrations. With electronic controlthat is stronger and faster than mechanics, precise regulationcompensates for periodic vibrations like torque ripple, maintainingsmooth and quiet rotor motion. For example, torque ripple is an artifactof the EiP modular magnetic design, where the linearization of a rotarymachine lacks the mechanical stabilization of a central shaft. Asmoothing algorithm in the VSC simulates control from the central shaftby cancelling and neutralizing torque ripple in real-time.

4.3. Exemplary EiP Wave Machine Oscillator Architecture

In various embodiments, the inductors in the EiP machine are the samesize, so two or more (e.g., all) generating PMLSMs with a diode bridgemust be connected in series for high voltage DC output. The resultingcircuit is the EiP oscillator, where the output of three or more PMLSMsin series, drive one PMLSM with a VSC through a voltage to voltageconverter from the HVDC to VSC DC link. This provides essential feedbackfor EiP oscillation and defines the electronic circuitry for the EiPwave machine. EiP technology breaks down a complex array of stators andelectronics into an EiP oscillator configuration, to form a synchronousgenerator of any size. One PMLSM controls rotor inertia (speed) usingmotoring thrust in either direction, maintaining a nominal speed windowwithin which EiP oscillation occurs. The control interface is a fiberoptic connection to the embedded digital signal processor (DSP) in themotoring PMLSM. FIG. 4C shows a schematic diagram of an exemplary EiPoscillator for an EiP wave machine.

4.3.1. Networked Control and Monitoring Interface

For external control, a fiber optic control network interface provides away to organize multiple EiP wave machines, through a central controllerdevice. The controller interacts with the user and other EiP wavemachines connected to the onshore DC aggregation point, through networkcommands.

5. System Architecture

The EiP wave machine is designed to operate within the context of adistributed generation system. The generation system can include anarray of EiP wave machines interfaced with an array of OWC devices alongthe length of a breakwater (e.g., off-shore array), connected to acommon power aggregation point onshore where power is managed for gridintertie. In some implementations, for example, the generation systemcan include an array of EiP wind machines located on-shore and connectedto the common power aggregation point. The grid side connects to otherdistributed generation stations in the area via shared transmissiongrid. This section discloses example embodiments of an EiP powergeneration system and describes how EiP technology advances the idea ofdistributed generation, which has been around since the late 1970s.However, several technical issues have prevented its widespreadadoption. For example, power quality—Multiple generators on a commongrid causes out of step conditions from poor synchronization, withexcessive electrical noise and harmonics. For example, poweroscillations—Interconnected rotating machines independently speed up andslow down under changes in load, causing uncontrollable, destructive andnon-linear behaviors like parasitic oscillations. For example,maintenance and reliability—Decentralization of power sources means morepotential points of failure that need to be serviced. For example, noiseand air pollution—Backup gensets all over town, using fossil fueledinternal combustion engines, drive generators at high RPM, which is loudand toxic.

5.1. Distributed Generation and the Disclosed Wave Power Technology

The disclosed technology provides all of the critical building blocksfor distributed generation in a marine renewable energy network, solvingall of the technical problems described above through the following. Forexample, networked hi-speed self-commutating converter electronics forsharing power at the DC level, delivering seamless power regardless ofresource availability and system load. For example, oscillation whenmultiple generators interconnect is a resource that enhances capture andstorage of renewable energy, allowing rotor speed to fluctuate bydesign. For example, fault tolerant, redundant, modular design, whereoperation continues, although at lower power, when individual componentsfail; network monitoring detects maintenance issues for service duringscheduled intervals, so power disruptions to local consumers areeliminated during extreme weather events. For example, massivelyparallel architecture where EiP wave machines operate with EiP windmachines, solar panels, and fuel cells onshore; transparent reliabilityeliminates the need for a noisy backup genset, placing dirty and noisypower plants away from residential areas (closer to bio-fuel sourcese.g., dairy farm, sewage treatment facility, garbage dump).

5.1.1. Exemplary EiP Distributed Generation Station

Onshore, as part of a 100% renewable power grid, the EiP DistributedGeneration Station, which in some embodiments can include the exemplaryEiP wind machine as its centerpiece, receives power from the offshoremarine renewable energy network and prepares it for local powerdistribution, along with other power sources and storage, as shown inthe diagram of FIG. 5A. FIG. 5A shows a diagram of an exemplary EiPdistributed generation system architecture. The system includes one ormore EiP wave machines 100 interfaced with corresponding OWCs, in whichthe EiP wave machines provide the converted electrical energy to anaggregation point 515. For example, the aggregation point 515 caninclude energy storage units and electrical and optical communicationlinks (e.g., DC power cables and fiber optic cables) to transfer theenergy to the power network, e.g., including other aggregation points,facilities, power generators and distribution centers, etc. For example,FIG. 5B shows a group of EiP wave machines, located offshore, and wiredin series to create a high voltage DC line to the shore-side aggregationpoint, which in this example includes an array of EiP wind machines. Theexemplary EiP wind machines can be tapped individually and connected tosynchronous inverters for distribution to EiP distributed generationstations through the disclosed three phase shared power feeds betweenvarious points on the network.

The exemplary EiP wave machine can be integrated with EiP windtechnology (i.e., one or more EiP wind machines 600) in the EiPdistributed generation system, e.g., to extract useful energy from gustyand turbulent urban wind conditions in an urban setting onshore. As withthe EiP wave machines 100, the EiP wind machines 600 are not only powergenerators but also operate as energy converters, where high inertiabacks up raw energy produced from wind and auxiliary sources withtemporary storage from which consumer power is sourced. EiP spontaneousnetworking technology links up with EiP wave machines 600 offshore tofully integrate and fine tune all power sources.

The EiP distributed generation station creates compact islands ofreliable and uninterrupted power, ideal for hi-technology. For example,the system architecture provides shared three-phase power betweenstations, which may be subject to disruptions, while distribution linesto consumers are isolated from the shared side, so network-widedisturbances have no effect on rate payers. This provides instant backupwhen faults occur, for example a powerline severed by a falling tree.The “Distributed Generation Intertie” block includes rectifiers thatconvert incoming AC to DC (e.g., equal to peak AC voltage), connectinggrid energy to the DC link. Generated AC is returned through asynchronous inverter on the DC link.

5.1.2. Using Oscillation as a Storage Mechanism

Whenever multiple sources of electrical generation are interconnected,oscillations are commonplace. Generators speed up and slow down underchanges in load, feeding back power surges and sags on one another tocreate parasitic oscillations. As a primary design feature, EiPtechnology converts the oscillation phenomenon into a resource thatimproves the capture, storage, and delivery of renewable energy.

EiP machines decouple the generator rotor angle from power delivery andinterconnect at the DC level, allowing rotor speed to fluctuate in“transient stability”: rotor operates at variable speed that is allowedto oscillate, normally a catastrophic failure mode when multiplegenerators connect out of step at the AC level. Changes in load andresource can naturally occur without storing or shedding excess power.An electronic inverter delivers the power providing instantaneous powerfactor control and correction, which determines how much power isactually consumed (resistive or “active” power) vs. power for magneticfields required to transmit and distribute it (reactive power).

For network-wide storage enhancement, several (at least four) EiPdistributed generation stations, operating in parallel on the sharedgrid segment, bounce excess inertial power between each other, causingrotor speed to go up and down in a system-wide oscillation that sustainsitself under base load. Since total inertia increases exponentially,slight changes in each EiP machine's rotor speed represent a largereservoir of potential energy network-wide, which is shuttled betweenEiP distributed generation stations.

Natural oscillation is self-sustaining, drawing energy from theenvironment in which it occurs, overcoming frictional forces and dragthat would otherwise cause rotor speed to slow, extending storage timetoward infinity. Power oscillations on the grid are commonplace,difficult to control, and impossible to eliminate, consuming usefulgenerated power. EiP technology simply converts this common non-linearphenomenon into a storage device; a hallmark of sustainability.

Once EiP oscillation takes hold, and spotty renewable power sources failto provide enough energy, less backup power from the shared grid isrequired to sustain oscillation, along with all loads present on thelocal distribution grid. Total inertia provides the greater powersource, using only a slight amount of backup power to keep electronicsrunning in each EiP machine. This provides further improvement in gridefficiency, well beyond unity power factor operation.

5.1.3. Isolating Disturbances On Transmission Lines From Consumer Power

EiP distributed generation architecture places power generation near thepoint of use. In this way, raw power (of low quality and reliability)from remote sources like marine renewable energy, does not directlyaffect consumer power. Distant power is received in raw form andregenerated as DC power by EiP each distributed generation stationsharing the transmission line. Then, electronic inverters provide AC tolocal consumers. One inverter need not power a whole distributionsystem. Each consumer circuit can have its own inverter, sharing acommon DC connection in the EiP distributed generation station. Atightly regulated and totally reliable power service is the result,which never fails from falling power lines.

5.2. Marine Renewable Energy Network

Ocean waves contain vast energy, with wave fronts hundreds of mileslong. But a single OWC installation captures only a differential amountof an infinite resource. To create utility scale power requires anetwork of OWC powerplants, integrating power from wave fronts all alongthe coast. Through EiP technology, EiP wave machines form spontaneousnetworks that maximize energy extraction along the entire wave front.FIG. 5B shows how the offshore EiP wave machines connect in series toform a high voltage DC (HVDC) transmission system, in combination withan array of onshore EiP wind machines, to form the marine renewableenergy network. Offshore and onshore, steady voltage regulation isprovided by EiP oscillation between all wave and wind machines. In thisscenario, there are no losses associated with transformers, simplydirect connected HVDC. Onshore, each EiP wind machine provides a way totap into transmitted power without transformers, directly to the DClinks of PMLSMs grouped as EiP oscillators. Unlike transformer basedHVDC transmission, which is naturally lossy, power is reinforced by thecombined EiP oscillation of offshore and onshore EiP machines toincrease the total energy of the transmission system.

EiP technology is fractal by design. At all levels, from PMLSM modulesto clusters of EiP wave machines, there is self-similarity in basicstructures and relationships. Clusters of EiP wave machines formspontaneous networks in groups of three or more, sharing common powerconnections with nearby OWC sites, linked by a high-speed fiber opticconnection. Groups of clusters form clusters in a wide area network. Thefractal expansion of modular structures presents no limits to the sizeand scope of a marine renewable power generating system, which isadaptable to natural geometries of shorelines. The prime focus of marinerenewable energy network design is to be part of a vibrant andproductive near-shore marine environment, without harm to the localecosystem and all who depend on it. The fractal nature of EiP technologyresembles how native ecosystems are constructed, in a self-organizingway.

5.2.1. EiP Spontaneous Networking

EiP spontaneous networking, embedded in each EiP wave machine, allowshi-speed control and monitoring system-wide, based on real-time feedbackfrom all other EiP machines in the network. EiP spontaneous networkingprotocol contains timing signals presented as data, in a constant streamthat operates like a hardware cache rather than a send-acknowledgeprotocol. One each EiP machine is operating at speed, it uses timingsignals from the network to fully synchronize operations with allothers, in parallel real-time, sensing pending power faults and takingcorrective action for system-wide power regulation.

In some examples of EiP spontaneous networking, for example, a minimumof four EiP wave machines, sharing their remote control and monitoringinterfaces over a fiber connection with low latency, self organize toform an EiP spontaneous network around the aggregation point. EiPmachines use power semiconductor technology rather than transformers,they can link in parallel at high voltage with low loss over buriedpower lines. The combined current and inertial storage of many EiP wavemachines increases local grid capacity and stability, through instantsharing of power with maximum efficiency in an EiP spontaneous network.On the EiP spontaneous network, groups of four EiP wave machines link upas “clusters”, to form one segment of the marine renewable energynetwork, segments link to form clusters of clusters, expanding thenetwork to generate power from the local shoreline with maximumefficiency and least environmental impact. Through EiP technology,efficiency and stability increase with system size, while fitting intothe local ecosystem.

5.2.2. EiP Network Nodes and Clusters

In this example, an EiP spontaneous network requires at least four EiPwave machines to form a network. Each EiP wave machine is a network“node”. Groups of four nodes form “clusters” on the network, organizedin direct association with the local terrain. Net connections aretetrahedral, with three network paths from node to node. Clusters formgroups of clusters, encompassing a wider geographical area.

5.2.3. Hardware Cache Line-based Network Protocol

EiP network protocol operates like a hardware cache, where thestructuring of data in the bit stream controls packet switching, at thenode level. The stream is synchronous with embedded timestamp. Allparticipating nodes follow the protocol, enforced by hardware. Anynon-conforming transactions are ignored and overwhelmed by the wholenetwork.

Each EiP wave machine broadcasts its current status to the network, thenlistens for others who share the same DC connection. Each EiP wavemachine is calibrated to its location, through common natural referencesfrom a geographic information system (GIS), from which a uniqueidentifier on the network is created. Like any self-organizing system innature, groups of nearby EiP wave machines coalesce, from which allderive control signals for local power management. EiP protocol operateswithout centralized addressing, providing a live picture of real-timerenewable power conditions across a wide area. Each node monitors systemconditions from its own localized perspective, and providesinstantaneous compensation for network-wide disruptions. EiP spontaneousnetworking creates a power web that eliminates grid lossiness fromtransformers and long transmission lines, through a softer approachbased on localized timely power control, rather than brute forcereactive power from huge powerplants.

The network is always operating at maximum speed and data throughput.While idle, the network data contains a diagnostic test pattern,indicating current network status and power conditions. Once running thenetwork is always fully loaded with real-time data. Each node waits forthe correct time slot for sending commands and status, overwritingexisting data without disrupting others.

5.2.4. Private Channel for Power Providers

Each EiP machine has access to a slot in the data stream for encryptedprivate transactions on the network. Other machines of common ownershipuse the private channel to meter and monitor for billing purposes. AllEiP machines group in a spontaneous way for maximum energy efficiency,while many distributed private monitoring and billing systems can managemonetary and statistical operations without affecting service quality.

5.3. EiP Synchronous Power Web

In combination with distributed generation stations, with EiP windmachines, solar panels, and fuel cells onshore, for example, the marinerenewable energy network of EiP wave machines can produce 100% renewableenergy in any conditions, storm or calm, day or night. This isaccomplished by a slow buildup of inertia, which is quickly released forbrief moments as needed to help maintain inertia in other EiP machinesin the network. Over time, enough inertia accumulates to power necessaryloads indefinitely, as excess inertia is shared by a “ping pong” effect.Hydrogen for fuel is created from water and excess power, and stored. Asconditions dictate, fuel cells sustain DC voltage and inertia in allconnected EiP machines.

5.3.1. Linking EiP Spontaneous Networks for Wide Area Energy Sharing

EiP spontaneous networks that share a data connection while operating onseparate grid segments link up to create a synchronous power web over alarge landscape. This solves the problem where the wind is blowingduring off peak times, and excess energy must be stored for peak times,even during calm. Through each spontaneous network, EiP wave machinesshare excess energy in a grid segment wide EiP oscillation, whichprovides a vast storehouse of energy.

When EiP spontaneous networks link up to form a power web, distanttransmission lines between can be allowed to operate wildly, asdisturbances are relayed by high speed data links and compensated for inadvance. The synchronous power web acts like a power filter, stabilizer,and battery for distant power generation from random renewable sources,without the need for flexible cogeneration, for maximum airflow power inthe energy mix.

5.4. EiP Wind Machine

FIGS. 6A and 6B show three-dimensional views of an exemplary EiP windmachine 600. FIG. 6C shows a cross-sectional diagram of the lowerportion of the EiP wind machine 600. The EiP wind machine 600 includes asupport base 620 to support an electronic inertial power generation unit610 of the disclosed technology. The support base 620 can include aplurality of struts positioned along the outside region of a base frame,which supports the electronic inertial power generation unit 610. Insome implementations, for example, the support base 620 can include aplurality of legs 625 to raise the support base 620, and thereby the EiPwind machine 600, to a desired height. The electronic inertial powergeneration unit 610 includes an annulus ring track 612 able to attach tothe base support 620 and structured to provide a circular track aroundwhich a circular array of inductors 602 (e.g., inductor coils) islocated. For example, the inductors 602 of the array are fixed inposition in the annulus ring track 612 over the support base 612 in acircular array. The electronic inertial power generation unit 610includes rollers (e.g., track roller bearings) placed in the circulartrack of the annulus ring track 612 to roll in the circular track tomove around the annulus ring track 612. In some embodiments, forexample, the annulus ring track 612 includes an upper inductor supportring 612A that contains the upper half of the inductor array, and theannulus ring track 612 includes a lower inductor and bearings supportring 612B, which contains the lower half of the inductor array. In someimplementations, for example, the struts of the support base 620 areattached to the upper and lower support rings 612A and 612B to provide agap (e.g., a fraction of an inch (e.g., ⅛ in) to a half of an inch, suchas 0.2 in.) for a magnetic rotor annulus to rotate between the upper andlower inductors contained in the upper and lower support rings 612A and612B.

The electronic inertial power generation unit 610 includes an annulusring rotor 614 placed on the annulus ring track 612 and engaged to therollers along the circular track of the annulus ring track 612. Forexample, in some implementations as shown in FIG. 6C, the annulus ringrotor 614 is configured between the upper support ring 612A and thelower support ring 612B of the annulus ring track 612, in which thelower support ring 612B includes the rollers (e.g., track rollerbearings) that support a bearing track ring of the annulus ring rotor614. For example, the bearing track ring can be structured to have twofaces perpendicular to one another, such that one face is engaged withthe rollers (e.g., track roller bearings) of the annuls ring track 612,and the other perpendicular face extends downward from the annulus ringrotor 614's lower surface. For example, the annulus ring track 612 caninclude horizontal rollers (e.g., horizontal guide bearings) that engagethe perpendicular portion of the bearing track ring (e.g., roll aboutthe perpendicular track of the bearing track ring) to guide the rotationof the annulus ring rotor 614 to maintain its position in the x-y planeas it rotates with respect to the inductor arrays of the annulus ringtrack 612. The annulus ring rotor 614 can rotate relative to the anannulus ring track 612, e.g., by operation of rolling motion of therollers in the circular track, without having a rotary shaft in thecenter of the annulus ring rotor for rotating the annulus ring rotor614. The annulus ring rotor 614 is structured to include separatemagnets 604 evenly spaced from one another on the annulus ring rotor 614(e.g., on an outer peripheral of the annulus ring rotor 614) to movethrough the circular array of inductor coils (e.g., between the upperand lower inductor arrays) as the annulus ring rotor 614 rotates overthe annulus ring track 612, e.g., so that the relative motion betweenthe magnets and the inductor coils causes generation of electriccurrents in the inductor coils.

The electronic inertial power generation unit 610 includes a cylindricalwind rotor assembly 616 located above and coupled to the annulus ringrotor 614, e.g., which forms a unified assembly, to rotate with theannulus ring rotor 614 relative to the annulus ring track 612. The windrotor assembly 616 is structured to include a plurality of wind rotorblades 617 (e.g., wind-deflecting blades) that are spaced from oneanother and arranged in a circle around the wind rotor assembly 616 toform a hollow central cylindrical interior space for containing a windvortex formed from deflecting of the received wind by thewind-deflecting blades 617. The wind rotor assembly 616 is operable toconvert received wind, e.g., received from any direction, into arotation of the unified assembly relative to the annulus ring track 612,thus causing conversion of the wind energy into the electric currents inthe inductor coils, and thereby producing electrical energy. Forexample, in some implementations of the wind rotor blades 617, thewind-deflecting blade can have a structure including a curved bladeportion to deflect the received wind into a wind vortex inside a hollowcentral region of the cylindrical wind rotor assembly. For example, thecurved blade portion in each wind-deflecting blade can have a geometryof a portion of a cylinder. For example, the curved blade portion ineach wind-deflecting blade can include a geometry of one third of acylinder.

As shown in the diagrams of FIGS. 6A and 6B, the electronic inertialpower generation unit 610 can include a cylindrical wind stator assembly618 that is configured in a fixed position relative to the support base620 and the annulus ring track 612. The wind stator assembly 618includes stator wind-receiving fins 619, e.g., arranged in a circle thatis outside of and encloses the cylindrical wind rotor assembly 616. Thestator wind-receiving fins 619 are structured to direct received windfrom any direction inwards and towards the wind-deflecting blades 617 ofthe cylindrical wind rotor assembly 616. The stator wind-receiving fins619 and the wind-deflecting blades 617 are structured to collectivelyand efficiently convert the received wind into a rotation of thecylindrical wind rotor assembly. In some embodiments of the wind statorassembly 618, for example, the stator wind-receiving fin 619 include apipe or rod having a curved outer edge as a first interface of the windpower generator with the received wind. For example, the statorwind-receiving fin can include a fin portion that is slanted inorientation with respect to a radial direction of the cylindrical windstator assembly and is configured to receive and direct wind into thewind-deflecting blades of the cylindrical wind rotor assembly. Forexample, the fin portion can be configured to be slanted in orientationwith respect to a radial direction of the cylindrical wind statorassembly at 45 degrees.

For example, the stator wind-receiving fins 619 can include a finportion formed of a metal or metallic alloy, e.g., such as an aluminumfin portion. In some embodiments, for example, the stator wind-receivingfins 619 and the wind-deflecting blades 617 are configured so that aradial dimension of the cylindrical wind stator assembly 618, a radialdimension of the cylindrical wind rotor assembly 616, and a radius ofthe hollow central cylindrical interior space 611 in the center of thecylindrical wind rotor assembly 616 are substantially the same. Forexample, the cylindrical wind stator assembly 618 can be configured tohave an outer diameter greater than a length of the cylindrical windstator assembly along a cylindrical axis of the cylindrical wind statorassembly. In some embodiments, for example, the number of the statorwind-receiving fins 619 of the cylindrical wind stator assembly 618 canbe configured to be greater than a number of the wind-deflecting blades617 of the cylindrical wind rotor assembly 616. In some embodiments, forexample, each wind-deflecting blade 617 includes a curved blade portion,and the stator wind-receiving fins 619 are slanted in orientation withrespect to respective radial directions of the cylindrical wind statorassembly 618 to direct received wind towards a concave side of thecurved blade portion of each wind-deflecting blade 617.

Referring to FIG. 6C, for example, the electronic inertial powergeneration unit 610 can be structured such that the inductor coils inthe circular array of inductor coils are configured into independentinductor modules that operate independently from one module to another,in which example, each inductor module can include (1) three adjacentinductor coils that are connected to one another to form a 3-phaseinductor module to so that the phases of the three adjacent inductorcoils are separated by one third of a cycle to collectively produce anAC output current from three currents respectively generated by thethree adjacent inductor coils, and (2) a rectifier circuit coupled toreceive the AC output current and to produce a DC output voltage. Forexample, the rectifier circuit of an inductor module can include athree-phase diode bridge rectifier circuit formed of six diodes.

In some implementations, for example, the electronic inertial powergeneration unit 610 can be structured such that the inductor coils inthe circular array of inductor coils are configured as independentinductor modules that operate independently from one module to another,in which each inductor module includes (1) three adjacent inductor coilsthat are connected to one another to form a 3-phase inductor module toso that the phases of the three adjacent inductor coils are separated byone third of a cycle to collectively produce an AC output current fromthree currents respectively generated by the three adjacent inductorcoils, and (2) a rectifier circuit coupled to receive the AC outputcurrent and to produce a DC output voltage; and in which the inductormodules are configured as independent inductor module groups where eachinductor module group includes 3 or more inductor modules, the inductormodules within each inductor module group are coupled to produce aninductor module group output, and different inductor module groups areseparated and operate independently from one to another.

For example, each inductor module group can include a mode-switchingcircuit in a selected inductor module in the inductor module group andcoupled to a rectifier circuit of the selected inductor module toinactivate the rectifier circuit to allow the selected inductor moduleto operate in an AC mode for producing an AC output or to activate therectifier circuit to allow the select inductor module to operate in anDC mode for producing an DC output, and a control circuit coupled to themode-switching circuit to control the operation the mode-switchingcircuit in switching the selected inductor module between the AC modeand the DC mode. For example, each inductor module group can include asensing circuit coupled in the selected inductor module in the inductormodule group that senses a rotation condition of the cylindrical windrotor assembly based on timing and magnitudes of currents in theinductor coils within the selected inductor module and, based on thesensed rotation condition, the control circuit is configured to controlthe AC mode operation of the selected inductor module in response to thereceived wind condition to accelerate or decelerate the rotation of thecylindrical wind rotor assembly so that the rotation of the cylindricalwind rotor assembly varies dynamically with received wind condition tomaximize an efficiency in converting the received wind power intoelectricity.

In some implementations, for example, each inductor coil can include afirst half inductor coil part that includes a first magnetic core and afirst conductor wire coil that winds around the first magnetic core, anda second half inductor coil part that includes a second magnetic coreand a second conductor wire coil that winds around the second magneticcore, in which the first and second half inductor coil parts arepositioned at opposite sides of a plane in which the magnets in theouter peripheral of the annulus ring rotor rotate to position themagnets between the first and second half inductor coil parts. In someimplementations, for example, each of the first and second half inductorcoil parts can include a C shaped magnetic core having two terminal endsthat interface with the magnets in the outer peripheral of the annulusring rotor, and two adjacent magnets in the outer peripheral of theannulus ring rotor are placed in opposite magnetic orientations withrespect to each other. For example, the C shaped magnetic core can beconfigured to have the two terminal ends spaced from each other by aspacing of two adjacent magnets in the outer peripheral of the annulusring rotor.

In some implementations, for example, the control circuit can include adigital signal processor that is programmed with software to control,based on the sensed rotation condition from the sensing circuit, the ACand DC modes of operation of the selected inductor module in theinductor module group. In some implementations, for example, the controlcircuit can be configured to control the inductor coils within theselected inductor module to cause the rotation of the cylindrical windrotor assembly to be in a coasting mode which maintains a constant speedof the rotation of the cylindrical wind rotor assembly at a givenreceived wind condition and produces a DC output of the wind powergenerator, a motoring mode which speeds up the rotation of thecylindrical wind rotor assembly while reducing a DC output of the windpower generator, or a generating mode which slows down the rotation ofthe cylindrical wind rotor assembly while increasing the a DC output ofthe wind power generator. In some implementations, for example, thecontrol circuit is configured to control, based on the sensed rotationcondition from the sensing circuit, the selected inductor module tooperate in or switch to one of the coasting mode, the motoring mode, orthe generating mode to dynamically synchronize operation of the windpower generator to the received wind condition and a load condition thatdraws power from the wind power generator.

In a quiet, strong, and unimposing form, the EiP wind machine 600converts wind (e.g., rooftop wind) into stable electric power, from asingle moving mass rotating inside a stationary one. Wind enters themachine 600 from all sides, and exits through the top and bottom of thehollow core 611. The electronic inertial power generation unit 610 ofthe EiP wind machine 600 has no central shaft or mechanical connectionsother than wind, only electrical and networking interfaces.

Rapidly rotating lines of magnetic flux from permanent magnets in therotor generate electric power as they pass between stationary inductors.In some embodiments, for example, the EiP wind machine 600 can beconfigured to be approximately six feet in diameter, supporting eightymagnetic pole pairs (160 magnets). This exemplary embodiment representsa minimum practical size of EiP wind machine. EiP technology is scalableto much larger size and power.

Additional examples of the EiP wind machine and information pertainingto the EiP wind technology are disclosed in PCT Patent Application No.PCT/US2015/041204, entitled “DIRECT WIND ENERGY GENERATION” and filed onJul. 20, 2015, which is incorporated by reference in its entirety aspart of the disclosure in this patent document.

6. Programming Considerations

The disclosed technology can include programming of EiP machinenetworks, including PMLSM parameters and EiP spontaneous network datastructure. An exemplary EiP program environment can include DC networkand parameters, spontaneous network and cache line structure, and powerweb cache line, etc.

6.1. PMLSM Parameter Programming

In some implementations, EiP programming may depend on manufacturerspecifications. For example, in some implementations, an exemplary EiPwave machine can use Allen Bradley Powerflex 40 3-phase motorcontrollers.

6.2. EiP Spontaneous Networking Data Structure

EiP spontaneous networking data structure, which is applied tonetworking tools and techniques for three-phase industrial motornetworks, represents a cache line on the EiP spontaneous network thateach EiP wave machine constantly updates with current operating data.The EiP data structure (e.g., EiP Spontaneous Networking Data Structure)can include a time stamp, machine identifier, and operating mode.

EXAMPLES

The following examples are illustrative of several embodiments of thepresent technology. Other exemplary embodiments of the presenttechnology may be presented prior to the following listed examples, orafter the following listed examples.

In one example of the present technology (example 1), a wave powergenerator device to interface to an oscillating water column forconverting marine wave power into electricity includes a tube includinga support base on each end of the tube; a stator assembly including acircular array of inductor coils fixed in position in a cavity of thesupport base, an annular ring track coupled to the support base in thecavity and configured to provide a circular track around which thecircular array of inductor coils is located, and bearings placed on acircular annular bearing-ring track attached to the support base, thebearings operable to roll to allow a surface in contact with thebearings to move with respect to the annular bearing-ring track; and arotor assembly including an annular cylinder flywheel structured to forma hollow interior and an outer cylindrical wall having a wide thicknessto provide the annular cylinder flywheel with a high inertia, a turbinerotor attached to the annular cylinder flywheel at a particular planealong the hollow interior, the turbine rotor structured to include adisk and a plurality of blades protruding from the disk that passthrough the outer cylinder wall of the annular cylinder flywheel into acavity, and an array of magnets arranged to be evenly spaced and ofalternating axial polarity from one another protruding from the outercylindrical wall of the annular cylinder flywheel such that the magnetsmove through the circular array of inductor coils as the annularcylinder flywheel rotates with respect to the annular ring track so thatthe relative motion between the magnets and the inductor coils causesgeneration of electric currents in the inductor coils, in which therotor assembly is engaged to the bearings on the circular annularbearing-ring track so that the annular cylinder flywheel is operable torotate relative to the annular ring track by rolling motion of thebearings when airflow from wave energy enters the hollow interior of therotor assembly and causes the turbine rotor to rotate for conversion ofthe wave energy into the electric currents in the inductor coils, and inwhich the tube encases the rotor assembly and the stator assembly.

Example 2 includes the wave power generator device of example 1, inwhich the rotor assembly is configured without a rotary shaft in thecenter of the rotor assembly for rotating the rotor assembly.

Example 3 includes the wave power generator device of example 1, inwhich the rotor assembly is configured to have a diameter of at least 1meter.

Example 4 includes the wave power generator device of example 1, inwhich the hollow interior of the annular cylinder flywheel is structuredto provide a path for airflow to exit the rotor assembly.

Example 5 includes the wave power generator device of example 1, inwhich the tube is structured to include a pipe flange structure to allowattachment of the device to the oscillating water column.

Example 6 includes the wave power generator device of example 1, inwhich the tube is structured to form a set of threaded holes configuredto fit a standard pipe flange bolt pattern.

Example 7 includes the wave power generator device of example 1, thedevice further including an electronic module configured in a sealedcompartment of the tube positioned proximate and electrically coupled tothe circular array of inductor coils to receive the electric currentsfrom the inductor coils.

Example 8 includes the wave power generator device of example 1, inwhich the rotor assembly is operable to slowly spin based on an airflowto initially drive the turbine rotor and cause the rotor assembly torotate, such that during slow rotation of the rotor assembly magneticflux circulates at high speed through the through the circular array ofinductor coils to generate AC electric power.

Example 9 includes the wave power generator device of example 8, inwhich the generated AC electric power includes pure sinusoid AC power,in which voltage and frequency of the AC electric power increases withincreasing speed of the rotor assembly to provide synchronous power.

Example 10 includes the wave power generator device of example 9, thedevice further including a plurality of electronic modules configured ina sealed compartment of the tube positioned proximate and electricallycoupled to the inductor coils to receive the synchronous power, in whichthe electronic modules are wired together in series to provide a highvoltage DC output.

Example 11 includes the wave power generator device of example 1, inwhich the array of magnets includes 160 magnets with 80 magnetic polepairs.

Example 12 includes the wave power generator device of example 1, inwhich the inductor coils in the circular array are configured intoindependent inductor modules that operate independently from one moduleto another, in which each inductor module includes (i) three adjacentinductor coils that are connected to one another to form a 3-phaseinductor module to so that the phases of the three adjacent inductorcoils are separated by one third of a cycle to collectively produce anAC output current from three currents respectively generated by thethree adjacent inductor coils, and (ii) a rectifier circuit coupled toreceive the AC output current and to produce a DC output voltage.

Example 13 includes the wave power generator device of example 12, inwhich the rectifier circuit of an inductor module includes a three-phasediode bridge rectifier circuit formed of six diodes.

Example 14 includes the wave power generator device of example 1, inwhich the inductor coils in the circular array are configured asindependent inductor modules that operate independently from one moduleto another, in which each inductor module includes (i) three adjacentinductor coils that are connected to one another to form a 3-phaseinductor module to so that the phases of the three adjacent inductorcoils are separated by one third of a cycle to collectively produce anAC output current from three currents respectively generated by thethree adjacent inductor coils, and (ii) a rectifier circuit coupled toreceive the AC output current and to produce a DC output voltage, and inwhich the inductor modules are configured as independent inductor modulegroups where each inductor module group includes 3 or more inductormodules, the inductor modules within each inductor module group arecoupled to produce an inductor module group output, and differentinductor module groups are separated and operate independently from oneto another.

Example 15 includes the wave power generator device of example 14, inwhich each inductor module group includes a mode-switching circuit in aselected inductor module in the inductor module group and coupled to arectifier circuit of the selected inductor module to inactivate therectifier circuit to allow the selected inductor module to operate in anAC mode for producing an AC output or to activate the rectifier circuitto allow the select inductor module to operate in an DC mode forproducing an DC output, and a control circuit coupled to themode-switching circuit to control the operation the mode-switchingcircuit in switching the selected inductor module between the AC modeand the DC mode.

Example 16 includes the wave power generator device of example 15, inwhich each inductor module group further includes a sensing circuitcoupled in the selected inductor module in the inductor module groupthat senses a rotation condition of the rotor assembly based on timingand magnitudes of currents in the inductor coils within the selectedinductor module and, based on the sensed rotation condition, the controlcircuit is configured to control the AC mode operation of the selectedinductor module in response to the received airflow condition toaccelerate or decelerate the rotation of the rotor assembly so that therotation of the rotor assembly varies dynamically with a receivedairflow condition of compressed air within the rotor assembly tomaximize an efficiency in converting wave power into electricity.

Example 17 includes the wave power generator device of example 16, inwhich the control circuit includes a digital signal processor that isprogramed with software to control, based on the sensed rotationcondition from the sensing circuit, the AC and DC modes of operation ofthe selected inductor module in the inductor module group.

Example 18 includes the wave power generator device of example 16, inwhich the control circuit is configured to control the inductor coilswithin the selected inductor module to cause the rotation of the rotorassembly to be in (i) a coasting mode which maintains a constant speedof the rotation of the rotor assembly at a given received airflowcondition and produces a DC output of the wave power generator device,(ii) a motoring mode which speeds up the rotation of the rotor assemblywhile reducing a DC output of the wave power generator device, or (iii)a generating mode which slows down the rotation of the rotor assemblywhile increasing the a DC output of the wave power generator device.

Example 19 includes the wave power generator device of example 18, inwhich the control circuit is configured to control, based on the sensedrotation condition from the sensing circuit, the selected inductormodule to operate in or switch to one of the coasting mode, the motoringmode, or the generating mode to dynamically synchronize operation of thewave power generator device to the received airflow condition and a loadcondition that draws power from the wave power generator device.

Example 20 includes the wave power generator device of example 1, inwhich each inductor coil includes a first half inductor coil part thatincludes a first magnetic core and a first conductor wire coil thatwinds around the first magnetic core and a second half inductor coilpart that includes a second magnetic core and a second conductor wirecoil that winds around the second magnetic core, and the first andsecond half inductor coil parts are positioned at opposite sides of aplane in which the magnets of the outer cylindrical wall of the annularcylinder flywheel rotate to position the magnets between the first andsecond half inductor coil parts.

Example 21 includes the wave power generator device of example 20, inwhich each of the first and second half inductor coil parts includes a Cshaped magnetic core having two terminal ends that interface with themagnets of the outer cylindrical wall of the annular cylinder flywheel,and two adjacent magnets of the outer cylindrical wall of the annularcylinder flywheel are placed in opposite magnetic orientations withrespect to each other.

Example 22 includes the wave power generator device of example 21, inwhich the C shaped magnetic core is configured to have the two terminalends spaced from each other by a spacing of two adjacent magnets on theouter cylindrical wall of the annular cylinder flywheel.

Example 23 includes the wave power generator device of example 1, inwhich the array of magnets are attached on a surface of an annular ringstructure protruding from the outer cylindrical wall of the annularcylinder flywheel, such that the annular ring structure extends betweenthe annular ring track such that the magnets are aligned with thecircular arrangement of the array of inductor coils.

Example 24 includes the wave power generator device of example 1, inwhich the outer cylinder wall of the annular cylinder flywheel includestwo thick-walled cylinders made of

Example 25 includes the wave power generator device of example 1, inwhich the support base includes an opening on each side of the tube, andthe device further includes a detachable cover to allow access to theinterior of the device and to provide a watertight seal of the tube.

In one example of the present technology (example 26), a wave powergenerator device includes a tube frame including a hollow interior and afirst support base and a second support base on each end of the tubeframe, in which the first and second support bases are arranged to forma cavity along the peripheral of the tube frame; an array of inductorcoils positioned at in the cavity for each of the first and secondsupport bases; a plurality of bearings coupled to each of the first andsecond support base operable to roll to allow a surface in contact withthe bearings to move with respect to the inductor coils; an annularflywheel structured to include an outer cylindrical wall adjacent to thefirst and second support bases, the outer cylinder wall having a widethickness to provide the annular flywheel with a high inertia; a turbinerotor attached to the annular flywheel at a particular plane of thehollow interior, the turbine rotor structured to include a disk and aplurality of blades protruding from the disk, in which the turbine rotoris coupled to the outer cylinder wall of the annular flywheel; and anarray of magnets arranged to be evenly spaced and of alternating axialpolarity from one another, the array of magnets coupled to andprotruding from the outer cylinder wall of the annular flywheel andlocated in the cavity of each of the first and second support bases in agap between the inductor coils, in which rotation of the annularflywheel causes the magnets to move through gap between the inductorcoils such that the relative motion between the magnets and the inductorcoils causes generation of electric currents in the inductor coils, inwhich the wave power generator device is structured to be interfacedwith an oscillating water column, such that airflow expelled from theoscillating water column caused from wave energy is able to enter thehollow interior of the wave power generation device and affect rotationof the turbine rotor for conversion of the wave energy into the electriccurrents in the inductor coils.

Example 27 includes the wave power generator device of example 26, inwhich the tube frame includes a bearing-ring track attached to the firstand second support bases and coupled to the bearings to present thebearings such that they rotationally engage the surface of the outerwall of the annular flywheel.

Example 28 includes the wave power generator device of example 26, inwhich the generation of the electric currents in the in the inductorcoils of the wave power generator is based on rotation of the annularflywheel on the bearings at least initially caused by oscillatingairflow into and out of the hollow interior to initiate rotation of theturbine rotor in one direction, such that electric currents are producedbased on the interaction of magnetic fields from the magnets with theinductor coils during the rotation of the annular flywheel.

Example 29 includes the wave power generator device of example 26, inwhich the wave power generation device is interfaced with an oscillatingwater column that is operable to receive water waves to produce outwardairflow from the oscillating water column as a result of the receivedwater waves, such that the outward airflow is fed into the wave powergeneration device to affect the rotation of the turbine rotor forconversion of the wave energy into the electric currents in the inductorcoils.

Example 30 includes the wave power generator device of example 26, inwhich the wave power generator device is configured without a rotaryshaft in the center of the hollow interior or attached to the turbinerotor for rotating the turbine rotor.

Example 31 includes the wave power generator device of example 26, inwhich the hollow interior is structured to provide a path for theairflow to enter and exit the wave power generator device.

Example 32 includes the wave power generator device of example 26, inwhich the tube frame is structured to include a pipe flange structure toallow attachment of the wave power generator device to an oscillatingwater column.

Example 33 includes the wave power generator device of example 26, inwhich the tube frame is structured to form a set of threaded holesconfigured to fit a standard pipe flange bolt pattern to attach the wavepower generation device to the oscillating water column.

Example 34 includes the wave power generator device of example 26, thedevice further including an electronic module configured in a sealedcompartment of the first and second support bases positioned proximateand electrically coupled to the array of inductor coils to receive theelectric currents from the inductor coils.

Example 35 includes the wave power generator device of example 26, inwhich the annular flywheel is operable to slowly spin based on theairflow to initially drive the turbine rotor and cause the annularflywheel to rotate, such that during slow rotation of the annularflywheel magnetic flux circulates at high speed through the through thearray of inductor coils to generate AC electric power.

Example 36 includes the wave power generator device of example 35, inwhich the generated AC electric power includes pure sinusoid AC power,in which voltage and frequency of the AC electric power increases withincreasing speed of the rotor assembly to provide synchronous power.

Example 37 includes the wave power generator device of example 36, thedevice further including a plurality of electronic modules configured ina sealed compartment of the of the first and second support basespositioned proximate and electrically coupled to the inductor coils toreceive the synchronous power, in which the electronic modules are wiredtogether in series to provide a high voltage DC output.

In one example of the present technology (example 38), a method forgenerating electricity from water wave energy includes receiving waterwaves into an oscillating water column to produce an outward airflowfrom the oscillating water column as a result of the received waterwaves; receiving the outward airflow into an interior of a wave powergenerator device to affect rotation of a rotator assembly in the wavepower generator device, the device including a stator assembly and therotor assembly encased within a tube structure having a base frame ateach end of the tube structure, the stator assembly including a circulararray of inductor coils in a fixed position with respect to the baseframe in the cavity and a plurality of bearings coupled to the baseframe, and the rotor assembly including a turbine rotor having a centralhub and peripheral blades coupled to an annular flywheel that is engagedwith the bearings and an array of magnets arranged to be evenly spacedand of alternating axial polarity from one another protruding outwardlyfrom the annular flywheel and between the circular array of inductorcoils; and generating electrical power at the wave power generatordevice based on rotation of the annular flywheel on the bearings atleast initially caused by oscillating airflow into and out of theinterior of the rotor assembly to initiate rotation of the turbine rotorin one direction, such that electric currents are produced based on theinteraction of magnetic fields from the magnets with the inductor coilsduring the rotation of the annular flywheel, in which the rotationsteadily continues in absence of or reduced wave energy from the waterwaves.

Example 39 includes the method of example 38, in which the receiving thewater waves by the oscillating water column includes receivingsuccessive waves create an oscillating air flow into and out of the wavepower generator device while the rotor assembly continues the rotationin a constant direction and at a regulated speed fortified by theannular flywheel's inertia and electronic interactions to generate asteady electrical power output.

Example 40 includes the method of example 38, further includingtransferring the generated electrical power to a power aggregation pointof a power network, a power storage device, or a power consuming device.

Implementations of the subject matter and the functional operationsdescribed in this patent document can be implemented in various systems,digital electronic circuitry, or in computer software, firmware, orhardware, including the structures disclosed in this specification andtheir structural equivalents, or in combinations of one or more of them.Implementations of the subject matter described in this specificationcan be implemented as one or more computer program products, i.e., oneor more modules of computer program instructions encoded on a tangibleand non-transitory computer readable medium for execution by, or tocontrol the operation of, data processing apparatus. The computerreadable medium can be a machine-readable storage device, amachine-readable storage substrate, a memory device, a composition ofmatter effecting a machine-readable propagated signal, or a combinationof one or more of them. The term “data processing apparatus” encompassesall apparatus, devices, and machines for processing data, including byway of example a programmable processor, a computer, or multipleprocessors or computers. The apparatus can include, in addition tohardware, code that creates an execution environment for the computerprogram in question, e.g., code that constitutes processor firmware, aprotocol stack, a database management system, an operating system, or acombination of one or more of them.

A computer program (also known as a program, software, softwareapplication, script, or code) can be written in any form of programminglanguage, including compiled or interpreted languages, and it can bedeployed in any form, including as a stand-alone program or as a module,component, subroutine, or other unit suitable for use in a computingenvironment. A computer program does not necessarily correspond to afile in a file system. A program can be stored in a portion of a filethat holds other programs or data (e.g., one or more scripts stored in amarkup language document), in a single file dedicated to the program inquestion, or in multiple coordinated files (e.g., files that store oneor more modules, sub programs, or portions of code). A computer programcan be deployed to be executed on one computer or on multiple computersthat are located at one site or distributed across multiple sites andinterconnected by a communication network.

The processes and logic flows described in this specification can beperformed by one or more programmable processors executing one or morecomputer programs to perform functions by operating on input data andgenerating output. The processes and logic flows can also be performedby, and apparatus can also be implemented as, special purpose logiccircuitry, e.g., an FPGA (field programmable gate array) or an ASIC(application specific integrated circuit).

Processors suitable for the execution of a computer program include, byway of example, both general and special purpose microprocessors, andany one or more processors of any kind of digital computer. Generally, aprocessor will receive instructions and data from a read only memory ora random access memory or both. The essential elements of a computer area processor for performing instructions and one or more memory devicesfor storing instructions and data. Generally, a computer will alsoinclude, or be operatively coupled to receive data from or transfer datato, or both, one or more mass storage devices for storing data, e.g.,magnetic, magneto optical disks, or optical disks. However, a computerneed not have such devices. Computer readable media suitable for storingcomputer program instructions and data include all forms of nonvolatilememory, media and memory devices, including by way of examplesemiconductor memory devices, e.g., EPROM, EEPROM, and flash memorydevices. The processor and the memory can be supplemented by, orincorporated in, special purpose logic circuitry.

It is intended that the embodiments and implementations described in thespecification, together with the drawings, be considered exemplary,where exemplary means an example. As used herein, the singular forms“a”, “an” and “the” are intended to include the plural forms as well,unless the context clearly indicates otherwise. Additionally, the use of“or” may include “and/or”, unless the context clearly indicatesotherwise.

While this patent document contains many specifics, these should not beconstrued as limitations on the scope of any invention or of what may beclaimed, but rather as descriptions of features that may be specific toparticular embodiments of particular inventions. Certain features thatare described in this patent document in the context of separateembodiments can also be implemented in combination in a singleembodiment. Conversely, various features that are described in thecontext of a single embodiment can also be implemented in multipleembodiments separately or in any suitable subcombination. Moreover,although features may be described above as acting in certaincombinations and even initially claimed as such, one or more featuresfrom a claimed combination can in some cases be excised from thecombination, and the claimed combination may be directed to asubcombination or variation of a subcombination.

Similarly, while operations are depicted in the drawings in a particularorder, this should not be understood as requiring that such operationsbe performed in the particular order shown or in sequential order, orthat all illustrated operations be performed, to achieve desirableresults. Moreover, the separation of various system components in theembodiments described in this patent document should not be understoodas requiring such separation in all embodiments.

Only a few implementations and examples are described and otherimplementations, enhancements and variations can be made based on whatis described and illustrated in this patent document.

1.-25. (canceled)
 26. A method for converting water wave power intoelectricity, comprising: receiving water waves by an oscillating watercolumn interfaced with a wave power generator device, wherein thereceived water waves produce an airflow from the oscillating watercolumn; receiving the airflow by the wave power generator device;rotating a rotor assembly with respect to a stator assembly based atleast upon the received airflow entering an interior of the wave powergenerator device, wherein the rotor assembly includes a turbine rotor,an annular cylindrical flywheel attached to the turbine rotor, and anarray of magnets disposed on the rotor assembly where each magnet isarranged to be of alternating axial polarity with respect to anotheradjacent magnet, and wherein the stator assembly includes an array ofinductor coils fixed in position on a support base, an annular trackcoupled to the support base to which the array of inductor coils isdisposed, and a plurality of bearings to engage the annular cylindricalflywheel to allow the rotor assembly to rotate; generating electricalenergy by the wave power generator device caused by rotation of therotor assembly with respect to the stator assembly via movement of themagnets by the array of inductor coils as the annular cylindricalflywheel rotates with respect to the annular track so that the relativemotion between the magnets and the inductor coils causes generation ofelectric currents in the array of inductor coils.
 27. The method ofclaim 26, wherein the rotation steadily continues in absence of orreduced wave energy from the water waves.
 28. The method of claim 26,wherein the wave power generator device transforms mechanical torquewith high inertia to electromagnetic torque, thereby producing theelectrical energy via the rotation of the rotor assembly.
 29. The methodof claim 26, wherein the rotating a rotor assembly includes slowingspinning the rotor assembly based on an initial airflow received by thewave power generator device to initially drive the turbine rotor andcause the rotor assembly to rotate, such that, during slow rotation ofthe rotor assembly, magnetic flux circulates at high speed through thearray of inductor coils to generate the electric energy.
 30. The methodof claim 29, wherein the generated electrical energy includes ACelectric power comprising pure sinusoid AC power, wherein voltage andfrequency of the AC electric power increases with increasing speed ofthe rotor assembly to provide synchronous power.
 31. The method of claim26, wherein the rotor assembly is configured without a rotary shaft inthe center of the rotor assembly for rotating the rotor assembly. 32.The method of claim 26, wherein the interior of the wave power generatordevice provides a path for the airflow to exit the rotor assembly. 33.The method of claim 26, comprising: receiving the electric currents fromthe array of inductor coils at an electronic device, wherein theelectronic device is configured in a sealed compartment of the wavepower generator device and electrically coupled to the array of inductorcoils.
 34. The method of claim 26, comprising: operating two or more ofthe wave power generator devices interfaced to the oscillating watercolumn to receive air flows into the two or more wave power generatordevices for producing the electrical energy.
 35. The method of claim 26,wherein the wave power generator device further comprises a tubeincluding the support base and encasing the rotor assembly and thestator assembly, the tube being interfaced to receive the airflow fromthe oscillating water column.
 36. The method of claim 26, wherein thearray of inductor coils is fixed in position in a cavity of the supportbase, and the annular track is coupled to the support base in thecavity.
 37. The method of claim 26, wherein the annular cylindricalflywheel is structured to form a hollow interior and an outercylindrical wall having a wide thickness to provide the annularcylindrical flywheel with a high inertia.
 38. The method of claim 37,wherein the turbine rotor includes a disk and a plurality of bladesprotruding from the disk that pass through the outer cylinder wall ofthe annular cylindrical flywheel.
 39. The method of claim 26, whereinthe rotor assembly is configured to have a diameter in a range of 1meter to 1.4 meters.
 40. The method of claim 26, wherein each of theinductor coils of the array are independent from one another toindependently produce respective currents caused by the relative motionof the magnets relative to the inductor coils of the array so that afailure in one inductor coil is not disruptive to current generation inanother inductor coil.
 41. The method of claim 26, wherein the inductorcoils of the array are configured into independent inductor modules,wherein each of the independent inductor modules operates independentlyfrom other modules.
 42. The method of claim 41,wherein each of theindependent inductor modules includes (i) three adjacent inductor coilsthat are connected to one another to form a 3-phase inductor module toso that the phases of the three adjacent inductor coils are separated byone third of a cycle to collectively produce an AC output current fromthree currents respectively generated by the three adjacent inductorcoils, and (ii) a rectifier circuit coupled to receive the AC outputcurrent and to produce a DC output voltage.
 43. The method of claim 42,wherein each of the independent inductor modules are configured asindependent inductor module groups where each inductor module groupincludes three or more inductor modules, the inductor modules withineach inductor module group are coupled to produce an inductor modulegroup output, and different inductor module groups are separated andoperate independently from one to another.
 44. The method of claim 26,wherein the rotation of the rotor assembly is at a regulated speed basedon the annular cylindrical flywheel's inertia and electromagneticinteractions of the magnets and inductor coils to generate a steadyelectrical power output.
 45. The method of claim 26, comprising:transferring the generated electrical energy to a power aggregationpoint of a power network, a power storage device, or a power consumingdevice.